Will We Be Spooked by Snow?

Public weather briefing

An incoming low-pressure system from Canada will bring with it a slight chance for snow-showers in the forecast area tonight. The frigid cooldown expected for our Halloween Friday will begin around midnight with temperatures dropping from about 43 down to around 35 by 7am. Northerly winds will also begin to pick up around this time to around 30mph, and will maintain this speed throughout the day Friday. Expect clearing skies and cold temperatures, with a high of about 39 and a low down to a chilly 25. Wind chills will exacerbate these below-average temps, making the temperature feel more like 30 in the day and upper teens/low 20's at night. Clear skies and slower northerly wind speeds of around 10mph will dominate the weather Saturday with a high around 40 and a low in the lower 20's, again below seasonal averages. A shift from northerly to southwesterly winds begins bringing warm air to the region by the beginning of next week, bringing temperatures to the upper 40's/lower 50's as well as a moderate breeze of around 12mph. A chance for precipitation also presents itself late Monday afternoon as a surface cyclone centered over northern Minnesota with a frontal zone that extends to Texas begins to pass through southern Wisconsin, with a cold front passing through Tuesday that will cool temperatures down again into early Wednesday. Warm westerly winds will bring up the temperatures to the upper 40's/lower 50's again by late Wednesday afternoon.

Forecast 

Tonight. Mostly cloudy with clearing skies after midnight, a low near 32.  Northwesterly winds increasing to at least 25mph by the early morning hours.  30% chance of precipitation with trace accumulation.

Friday. Clearing conditions early morning will bring about mostly sunny skies and much cooler temperatures with a high around 40.  Strong northerly winds up to 35mph could make the temperature feel more around 30.

Friday night. Clear and cold. Low near 25 and weaker winds at 10mph.

Saturday. Clear throughout the day with a high in the lower 40's.  Slightly breezy with 10mph northerly winds tapering off to light and variable.  Low in the upper 20's overnight. 

Sunday. Mostly clear skies with westerly/southwesterly winds around 12mph. High in the upper 40's and a low in the upper 30's.

Outlook for Monday through Wednesday. Expect an increase in clouds as the day progresses Monday with continued westerly/southwesterly winds around 12mph.  A high in the low 50's and a low in the low 40's is expected with a 40% chance of showers late Monday afternoon. Tuesday will be cooler once again as a band of cold air moves in through the area with moderate westerly winds blowing in at around 15mph, high in the lower 40's and low in the upper 20's.  As the cold front passes, expect warmer temperatures by late Wednesday and into the night.[CONFIDENCE: MEDIUM]

Forecast Discussion

A strong shortwave ridge-trough couplet moving through the area at 500mb will be the primary influence for our weather over the next few days.  As the trough axis drops into northern Wisconsin from Ontario it will advect a strong area of positive curvature vorticity that is projected to pass over eastern Wisconsin in the early morning hours Thursday. This will bring us our greatest chance for precipitation by forcing upward vertical motion according to the QG omega equation over the four day period. The GFS model shows oscillating percentages of relative humidity (between 70% and 40%) in the southern Wisconsin area with more humidity to the west than the east, while the NAM model shows a more solid area of consistent relative humidity (around 60%) in the same area. This supports the possibility for cloud formation and precipitation, particularly in the southeastern portion of the state. However, the advection of cold air from the north will work against the vorticity advection by causing subsidence, hence providing some uncertainty as to whether or not to expect precipitation. Consideration of Q-Vectors and their convergence between the 900mb and 700mb levels indicates the likely hood of upward vertical motion over the eastern part of the state at this time. This leaves a good chance for precipitation Thursday night in that area. Forecasing up to .175in of accumulated precipitation by 12z Friday, NAM model seems to agree with this projection. The GFS model, however, shows trace amounts of precip anywhere in the state. The uncertainty from these factors is why our forecast confidence is medium. In any case, with the 5400m thickness line from the 500:1000mb layer extending well south of Wisconsin it is clear that any precipitation will likely include snow showers.

  
This ridge-trough couplet will continue to advect cold air into the Midwest well into Friday with northerly wind speeds blasting in at a consistent 23 mph. With the trough axis well downstream from us, skies will clear as the localized cold-air advection brings subsidence into the forecasting region. As the ridge axis passes through late Friday night and into Saturday morning we will see a decrease in the pressure-gradient force and thus weaker northerly winds tapering off to around 10 mph, finally minimizing to light and variable winds as the center of the ridge enters the area mid-day Saturday. Skies will remain clear with a slight warm-up Sunday as the ridge passes through and advects southwesterly wind at around 10 mph. This wind will persist into Monday, where the NAM model shows an upper-level trough moving into the region. This will cause divergence aloft due to curvature acceleration downstream of the trough axis. Positive vorticity advection into the northwestern part of the state supports possible vertical motion in that area, bringing clouds and possible precipitation later in the day. Finally, Tuesday will see another cooldown as a band of cold air extending south from a Canadian cyclone passes through the area with westerly winds blowing in at around 15 mph. Following the cold front will be some warm temperature advection from westerly winds late Wednesday driven by a short-wave trough to the northwest.

Cody Kuchinski
Craig Oswald

A Frighteningly Frigid Friday Around the Corner!

Public weather briefing

The current weather over Madison and southern Wisconsin is quite fair with mostly clear skies and seasonal temperatures.  Clear skies are expected to persist overnight with clouds increasing Thursday morning and becoming overcast by the afternoon.  Temperatures will remain pleasant during the day with a high near 51 and moderate westerly winds shifting northerly.  A temperature decrease is expected to begin late Thursday as an anticyclone to our west and a weak cyclone to our east begin funneling cold Canadian air directly into the heart of the mid-west.  This will also produce strong northerly winds in the coming days and a 20% chance of precipitation, mostly in the form of rain with a few flurries possible, Thursday night.  This blast of cold air will linger into Halloween Friday with a high temperature of 39 and a low near 25, well below average.  Wind chill will also become a factor Friday with consistent winds around 25mph during the day and 10mph overnight making it feel more like 29 during the day and 15 during the night.  Clearer skies will also return Friday and persist through the weekend.  Temperatures will gradually warm over the weekend, reaching the lower 50's by Monday, as a shift from northerly to southwesterly winds begins bringing warm air to the region.  A chance for precipitation also presents itself late Monday afternoon as a surface cyclone centered over northern Minnesota with a frontal zone that extends to Texas begins to pass through southern Wisconsin.  

Forecast 

Tonight. Skies becoming mostly cloudy after midnight with a low temperature near 34.  Westerly winds around 6mph

Thursday. Continued overcast conditions with a high of 51.  Westerly winds around 8mph with a shift to northwesterly later in the afternoon. 

Thursday night. Mostly cloudy with clearing skies after midnight, a low near 32.  Northwesterly winds increasing to near 18mph by the early morning hours.  20% chance of precipitation with trace accumulation.  

Friday. Mostly sunny and much cooler temperatures with a high around 39.  Strong northerly winds up to 25mph.  Clear skies overnight with a low near 25 and weaker winds at 10mph 

Saturday. Clear throughout the day with a high in the lower 40's.  Slightly breezy with 10mph northerly winds tapering off to light and variable.  Low in the upper 20's overnight. 

Outlook for Sunday through Tuesday.  Mostly clear skies will persist through Sunday with westerly/southwesterly winds around 12mph with a high in the upper 40's and a low in the upper 30's.  Skies will become cloudier as the day progresses Monday with continued westerly/southwesterly winds around 12mph.  A high in the low 50's and a low in the low 40's is expected with a 40% chance of showers late Monday afternoon. Tuesday will be cooler once again as a band of cold air moves in through the area with moderate westerly winds blowing in at around 15mph, high in the lower 40's and low in the upper 20's.[CONFIDENCE: MEDIUM]

Forecast Discussion 

Today's weather was primarily dominated by an anticyclone centered over southern Illinois, clearing the skies and bringing westerly winds at a moderate 5 mph. A strong shortwave ridge-trough couplet moving through the area at 500mb will be the primary influence for our weather over the next few days.  As the trough axis drops into northern Wisconsin from Ontario it will advect a strong area of positive curvature vorticity that is projected to pass over eastern Wisconsin in the early morning hours Thursday. This will bringing us our greatest chance for precipitation by forcing upward vertical motion according to the QG omega equation over the four day period. The GFS model shows oscillating percentages of relative humidity (between 70% and 40%) in the southern Wisconsin area with more humidity to the west than the east, while the NAM model shows a more solid area of consistent relative humidity (around 60%) in the same area. This supports the possibility for cloud formation and precipitation, particularly in the southeastern portion of the state. However, the advection of cold air from the north will work against the vorticity advection by causing subsidence, hence providing some uncertainty as to whether or not to expect precipitation. Consideration of Q-Vectors and their convergence between the 900mb and 700mb levels indicates the likely hood of upward vertical motion over the eastern part of the state at this time. This leaves a good chance for precipitation Thursday night in that area. Forecasing up to .175in of accumulated precipitation by 12z Friday, NAM model seems to agree with this projection. The GFS model, however, shows trace amounts of precip anywhere in the state. The uncertainty from these factors is why our forecast confidence is medium. In any case, with the 5400m thickness line from the 500:1000mb layer extending well south of Wisconsin it is clear that any precipitation will likely include snow showers.

  
This ridge-trough couplet will continue to advect cold air into the Midwest well into Friday with northerly wind speeds blasting in at a consistent 23 mph. With the trough axis well downstream from us, skies will clear as the cold-air advection brings subsidence into the forecasting region. As the ridge axis passes through late Friday night and into Saturday morning we will see a decrease in the pressure-gradient force and thus weaker northerly winds tapering off to around 10 mph, finally minimizing to light and variable winds as the center of the ridge enters the area mid-day Saturday. Skies will remain clear with a slight warm-up Sunday as the ridge passes through and advects southwesterly wind at around 10 mph. This wind will persist into Monday, where the NAM model shows an upper-level trough moving into the region. This will cause divergence aloft due to curvature acceleration downstream of the trough axis. Positive vorticity advection into the northwestern part of the state supports possible vertical motion in that area, bringing clouds and possible precipitation later in the day. Finally, Tuesday will see another cooldown as a band of cold air extending south from a Canadian cyclone passes through the area with westerly winds blowing in at around 15 mph.

Craig Oswald
Cody Kuchinski

Freakfest or Freezing Fest?

Public weather briefing

The passage of the cold front last night turned out to be drier than initially predicted. Madison received no precipitation at all, but temperatures dropped significantly overnight, with a low this morning of 48 degrees. Winds shifted to out of the west as well bringing significant cold air advection, which will drop the low tonight to around 36. The rest of the week will be much drier and cooler as the cyclone moves eastward and is replaced with a large high pressure system that will dominate much of the central plains and upper midwest. This means winds will be out of the west/northwest throughout the latter half of the week, keeping high temperatures in the upper 40s Wednesday with a chance at 50 on Thursday. Friday sees the development of a weak surface low over the region, which will bring even colder air down from Canada for Halloween weekend. This front brings the possibility for flurries Friday morning, but the rest of the weekend remains dry as the system moves southeast out of the forecast area during the day Friday. Better bundle up for Halloween festivities...it is going to be a cold one once again.

Forecast 

Tonight. Considerably drier and colder. Mostly cloudy with a low around 36. Winds out of west around 10 mph.

Wednesday. Patches of sun, but remaining mostly cloudy. Northwesterly winds up to 10 mph. Cool with a high around 47.

Wednesday night. Winds begin to die off, becoming calm after sunset. Low of 35.

Thursday. Mostly cloudy with a high of 50. Westerly winds pick up again, up to 10 mph in the evening. 

Friday. Best chance for precipitation in the early morning. Very cold, with a high in the upper 30s and the low dipping into the 20s after dark. Much windier, with winds out of north between 15 to 20 mph.

Outlook for Saturday through Monday. Temperatures generally remain seasonable or slightly below average, with Saturday being the coldest day of the weekend. Skies clear Saturday morning, staying dry through Sunday, with a high in the mid 40s. Slight warm up into the start of the work week, with a high Monday of 51. Winds remain much calmer throughout the weekend, gradually shifting to more southerly flow. [CONFIDENCE: MEDIUM]

Forecast Discussion

After the passage of the cold front from last night, the rest of the week remains much drier with predominant cold air advection on the back side of the cyclone. The forecast for precipitation was off, as the majority of frontogenesis did not occur until the front passed to the east of the forecast area. A huge ridge lingers to the west for much of the week, producing a broad anticyclone over our area that will lead to widespread weak subsidence throughout the region, seen in the GFS 700 hPa vertical motions (18Z Wednesday shown below). The 850 hPa temperature map shows that the temperatures will stay fairly consistent through most of the week as there is no clear temperature advection by the geostrophic winds occuring anywhere over Wisconsin.

The 300 hPa jet remains weak throughout North America, despite the strong ridge in the 500 hPa geopotential height. Flow will stay out of the west/northwest for the latter half of the week, gradually shifting to out of the north for the arrival of the cold outbreak forecast for Friday morning. This feature already looks to be more significant than initially predicted, with the temperature at 850 hPa at -10 Celsius at 18Z Friday. This means the warmest it could possibly get on Friday, according to this model output, is around 2 degrees Celsius, with temperatures likely even colder in the morning. Additionally, there will be positive differential vorticity advection and a weak maximum in temperature advection in the 900 to 500 hPa layer over our area, leading to ascent by the classical QG omega equation. Madison will also be well north of the 5400m 1000-500 hPa thickness line at that time (much different from the previous forecast), so if precipitation results over the forecast area, it will most likely be snow. However, it appears the maximum in ascent will be east of Wisconsin into central Michigan, so while we may see some flurries Friday morning, Michigan could very well see its first measureable snowfall of the year.

Alex Haugstad
Conner Hardesty

Another cold Halloween in store for Madison

Public weather briefing

After a beautiful Monday in the 70's, mother nature will bring back normal fall temperatures continuing through the week, with high temperatures dropping into the 50's. A surface cyclone currently centered over Madison will propogate eastward through the forecast area later tonight. The cold front associated with this cyclone will pass through Madison around 9pm tonight, with winds shifting from nearly southerly to westerly over a three hour period. This front will bring a chance for scattered thunderstorms before midnight, with precipitation becoming lighter and more scattered through the early morning hours. Higher winds will advect cold air out of the west starting on Tuesday, dropping the low Tuesday night to around 35 degrees. A broad anticyclone dominates the region for most of the rest of the week. Temperatures will be a bit lower than average, with highs only getting into the high 40's for Wednesday and a low Wednesday night in the mid 30s. Thursday warms up a bit with a high in the low 50s, but for Halloween on Friday a cold front pushes through that could bring low temperatures Friday night down into the 20s.

Forecast 

Tonight. Chance of showers, winds shifting to westerly around midnight at 10 mph. Temperatures dip with a low around 47.

Tuesday. Mostly sunny with winds out the west at 10 to 15 mph. Gradually dipping temps with high around 55.

Tuesday night. Partly cloudy with winds out of west at 10 to 15 mph.  Low in the high 30's.

Wednesday. Sunny, winds shift to northwesterly at 10 mph. High of around 47, low around 35.

Thursday. Partly sunny, temperatures stay fairly steady with high in low 50's, low in mid 30's. Light winds out of the west at 5 mph.

Outlook for Friday through Sunday. Clear skies and sunny on Friday with a high of 43 and low of 27 with winds out of the north at 10 mph. Clear conditions continue through Saturday, high in mid 40's again and low around 33, winds out of the south at 10 to 15 mph. Showers possible on Sunday, steady temps with high near 50, low around 40.  [CONFIDENCE: MEDIUM]

Forecast Discussion

The surface cyclone located over Madison will track northeastward between 6Z and 12Z Tuesday and strengthen considerably as it crosses into eastern Canada. 850 hPa frontogenesis has a local maximum at 0Z just west of Madison, indicating significant strengthening of the cold front associated with this cyclone as it passes through the forecast area. This is backed up by the GFS 700 hPa vertical motion between 0Z and 12Z Tuesday (6Z shown below), which clearly shows the development of a thermally direct circulation in the vicinity of the front. Since this development occurs largely after the front passes Madison, we will be in a broad region of subsidence Tuesday into Wednesday, clearing skies significantly after a potentially stormy night tonight due to precipitation associated with the front. The GFS has Madison getting about a tenth of an inch tonight, while the NAM is dry. Overall the models agree well on the development of the baroclinic zone in the next 24 hours, but the NAM puts the front east of our area before strengthening. So, our forecast confidence is medium, due to this disagreement. 

After the passage of this cyclone, a broad anticyclone will be over the region for much of the week. The 300 hPa jet is quite weak throughout North America, but there is a strong ridge bringing north-northwesterly flow to the area. The GFS 850 hPa temperature shows localized cold air advection over the forecast area all day Tuesday and into Wednesday morning, giving us clearer skies than earlier on Monday due to weak subsidence. Flow will then shift to be roughly zonal for the latter half of the week, with little likelihood for cyclogenesis upstream of the area indicated in either the GFS or the NAM. The final feature of interest is the development of a trough and coincident baroclinic zone in southern Canada Thursday night, which could result in some precipitation Friday morning due to differential vorticity advection induced by the intense northerly flow downstream of a ridge over the central plains. However, this term of the classical QG omega equation is opposed by very localized cold air advection over the same region, so any precipitation forecasted as a result of this is up to interpretation. At this time Madison is right around the 5400m 1000-500 hPa thickness line, so areas just north of the area have a good chance of seeing some flurries, but likely no accumulation.

Alex Haugstad
Conner Hardesty

Indian Summer on Tap for the Weekend

Public weather briefing

Clear and chilly conditions are in store for tonight, with lows dipping into the lower 30's; make sure to bundle up when watching in the Orionid Meteor Shower. A chance of rain moves in for Thursday, as a warm front will approach the area from the west. Warm weather is on tap for the latter half of the week as high temperatures will approach and surpass the 70 degree mark. A cold front will push in by the start on next week, relaxing temperatures to near average.

Forecast 

Tonight. Clear and cool, patchy frost possible.  Low in the lower 30's.

Wednesday. Sunny and warmer. Light winds. High 60. Low around 38.

Wednesday night. Increasing clouds and light winds, Low around 40.

Thursday. Increasing Clouds, slight chance of rain. Highs in the mid 50's.

Friday. Mostly sunny, Highs around 64.

Outlook for Saturday through Monday. After a partly cloudy start on Saturday, temperatures should rebound well with highs to around 70. Much of the same for the tail end of the weekend with temperatures in the low 70's and ample sunshine on Sunday.  [CONFIDENCE: HIGH]

Forecast Discussion

A broad region of warm air advection clips the area Wednesday, but since it is not localized, vertical motion and precipitation will not be associated with this feature.  On Thursday a chance of precipitation associated with an area of positive vorticity advection exists at 500hPa. The NAM pinpoints the largest maximum in advection in southern Wisconsin, giving Madison a chance a showers. The GFS puts down roughly a tenth of an inch of rain during this time period; a region in Iowa will see between a half inch and an inch.  The GFS model brings 850hPa temperatures to around 14 or 15 during the weekend. With an addition of around 10 (according the recent days) degrees Celsius for parcels brought down adiabatically, highs could reach the mid 70s by the weekend.

The alternating periods of cold and warm air advections through the weekend could lead to discrepancies in when 850hPa temperatures will be a their peak, during the day or during the night. The timing of a strong cold front on Monday will certainly play a role in the tail end of the weekend and forecast period. 

Alternating Periods of Sun, Clouds, and Rain

Public weather briefing

We will remain dry tonight, however a chance of rain returns on both Friday night and Sunday night. Periods of sunny skies will make welcomed appearances Thursday and Saturday, and full sun is expected Tuesday and Wednesday. We will see typical mid-October temperatures for most of the week, except for a chilly Saturday with a chance of frost in the morning.

Forecast 

Tonight. Skies will remain clear. Low in the mid 40s. 

Friday.Skies becoming cloudy later in the day. High around 60.

Friday night. A chance for rain early in the evening. Low around 40.

Saturday. Cloudy skies with clearing later in the day. High in the lower 50s, low in the lower 30s.

Sunday. Some clouds. A small chance for rain very late. High in the upper 50s, low in the mid 30s.

Outlook for Monday through Wednesday. Dry except for a chance of rain early Monday. Highs in the mid to upper 50s with lows in the lower 40s. [CONFIDENCE=MEDIUM]

Forecast Discussion

High pressure will remain over our area tonight. Weak positive vorticity advection Friday night will force weak vertical motion that may lead to some precipitation. Winds from west to north Friday night, bringing significant cold air advection into the region on Saturday. Positive vorticity advection will work its way into the region Sunday night into Monday, producing vertical motion and our best chance for precipitation.

The main issue affecting our forecast confidence is the track of the cyclone that comes into our area Sunday night. If it were to track further to the north, our chance for precipitation diminishes significantly.

Joshua Weber
Brandon Lipp

Clearing Out for the Weekend

Public weather briefing

After a mild and rainy beginning of the week, conditions will begin to clear up later on in the week.  The rainfall we experienced early this morning will have fully moved through making way for some chance of sun by Thursday.  Low temperatures over the weeknights will remain around the upper 40s, dipping down into the upper 30s by the weekend.  Daytime high temperatures will slowly decrease into the weekend with partly sunny skies.  Rain is unlikely this weekend, but winds will be expected to pick up.

Forecast 

Tonight. Clearing with winds from the northeast around 11 kts. Lows in the upper 40s.

Wednesday. Mostly cloudy small chance of light rain. Highs in the mid 50s.

Wednesday Night. Cloudy and cool with light northerly winds.  Low in the mid 40s.

Thursday. Sun begins to appear. Moderate southwesterly winds of about 7 kts. High 65. Low around 48.

Friday. Clouds move back through the Madison area. Westerly winds about 17 kts. High 56. Low around 44.

Outlook for Saturday through Monday. Mostly cloudy with some sun.  No significant chance of rain.  Highs in the low to mid 50s on Saturday and Sunday and around 50 on Monday. Lows consistently in the upper 30s. [CONFIDENCE: MEDIUM]

Forecast Discussion

The cyclone has moved south of Madison and will avoid most of the Wisconsin area. Overcast conditions remain until Thursday. Winds begin to pick up on Friday as a separate cyclone moves across Canada to the north of Minnesota/Wisconsin. There is no significant rain expected for the rest of the week.  (average daily high temperature for later in the week around 60F; low 40F).

Our confidence for the weeks forecast was dampened by the remnants of the surface cyclone bringing a possible chance for rain in the next day.  There is also a forming cyclone to the north in Ontario, but does not indicate any bands of rain forming down in Wisconsin. We expect a dry and cool week ahead for the Madison area.

Rachel Down
Samuel Hartwick

Rainy Week Ahead

Public weather briefing

After a lovely weekend and a foggy Monday afternoon, rainy conditions and typically cool fall temperatures are anticipated for the week ahead.  The rainfall will begin tonight and persist through Wednesday across southeastern WI.  Heavy rain and deep clouds will continue throughout the week, fully clearing up on Friday.  Daytime high temperatures will remain moderate to mild throughout the week and slightly decrease on the weekend.  Pleasant conditions will linger into the next week.

Forecast 

Tonight. Overcast with strong winds out of the northeast. Chance of thunderstorms overnight. Low around 55.

Tuesday. Continued showers with rain accumulating to around 1-2". High around 61.

Tuesday night. Clouds remain; rain begins to lighten up. Low in the mid 40s.

Wednesday.  Rain tapers off around mid-afternoon. High mid to upper 50s. Low around 45 in the early morning.

Thursday. Showers possible in the morning. Clouds continue. High near 65.

Outlook for Friday through Sunday. Partly cloudy Friday, small chance of rain on Saturday, partly sunny Sunday.  Highs in the low 60s Friday and around 55 Saturday and Sunday. Lows around 40. [CONFIDENCE: MEDIUM-HIGH]

Forecast Discussion

A surface cyclone will be moving through the central United States, south of Madison this week.  Strong overcast conditions will stifle radiational cooling overnight.  As the cyclone moves to the northeast, it will bring rain to Madison through the middle of the week. The strongest effects of the warm and cold fronts associated with thickness advection will largely avoid the Madison area, resulting in mild temperatures. As the cyclone moves eastward, conditions will begin to clear by the end of the week, and through the weekend (average daily high temperature for later in the week 60F; low 40F).

The chances and amount of precipitation expected in Madison through the week come from analysis of the MOS data from the GFS. The most significant amount of precipitation is expected throughout Tuesday and continues into Wednesday evening. We expect the precipitation to move through before the weekend, making way for pleasant conditions Friday to Sunday.

Rachel Down
Samuel Hartwick

Beautiful Fall Weather Persists

Public Weather Briefing

**A Frost Advisory has been issued for Dane County until 1:00am Central Time Friday**

Delightful fall conditions will continue through the coming weekend. Daytime temperatures will continue to be in the mid 50s for the next week. Clear skies and light wind spell a recipe for frost Friday and Saturday morning. Perfect fall football weather this Saturday with minimal clouds, winds around 5mph, and a high in the upper 50s. A chance of rain comes in Monday morning, as much as .4inches, but conditions will return to those like this weekend on Tuesday morning.

Forecast 

Tonight. Clear skies, light winds of about 2-3mph. Low 36. Slight chance of frost.

Friday. Partly cloudy with winds around 5-8mph. High of 56.

Friday night. Calm, clear skies. Low 34. Chance of frost.

Saturday. Mostly sunny with high of 57. Light winds out of the south.

Sunday. Partly cloudy becoming overcast in the afternoon. Southerly winds of 10mph. High of 55.

Outlook for Monday through Wednesday. Cloudy through Monday into Tuesday morning with a moderate chance of precipitation Monday afternoon. Rain totals of .4 inches. Temps expected to remain in the mid 50s. [CONFIDENCE: MEDIUM]

Forecast Discussion

A surface anticyclone will enter the Madison area from the northwest Friday and Saturday, whose subsiding air and dry conditions further substantiates our calls for frost. Moving into Monday, we expect a trough axis to form west of our area through Minnesota. As this formation is typically associated with downstream upper ageostrophic divergence, we can expect some vertical motions to help support the possibility of rain. Also supporting our claim is the warm air advcetion from the wave to our west. The 300mb GFS analysis shows a weak jet entrance over our area, which could create more vertical forcing for precipitation.

Daniel Knuth
Rebecca Schultz

Beautiful Fall Weather Persists

Public Weather Briefing

This crisp, fall air is here to stay! The clear skies, moderate, shifting winds, and high temperatures in the upper 50s that dominated the past few days will continue into later this week and through the upcoming weekend. Low temperatures tonight and tomorrow night look cooler, with daytime highs remaining pleasant. Wind speeds will stay moderate through the end of the week and into the weekend. Clear skies overnight Thursday will present favorable conditions for frost early Friday morning, with identical conditions occurring Friday night into Saturday morning. Clear skies look to dominate for the Badger football on Saturday, with temperatures nearing 50 at kickoff. Cloudy skies and chances of precipitation enter the region Saturday night and look to remain into early next week.

Forecast 

Tonight. Party cloudy with light westerly winds. Low around 40.

Thursday. Clouds clearing in the afternoon hours. High around 56 with moderate winds.

Thursday night. Clear skies may give way to overnight frost. Low around 38.

Friday. Lingering frost in the morning will give way to party cloudy skies in the afternoon. Moderate winds with a high around 55.

Saturday. Mostly sunny skies will make for a beautiful Badger Saturday. Temperatures at kickoff nearing 50, with a high of 57. Winds light and variable.

Outlook for Sunday through Wednesday. Clouds roll in Saturday night and stick around into early next week. Earliest rain chances Sunday afternoon, with lingering chances remaining Monday and Tuesday. High temperatures stay in the upper 50s, with overnight lows dropping into the middle 40s. [CONFIDENCE: HIGH]

Forecast Discussion

The well-defined cyclone situated over western Ontario will remain generally immobile, slowly moving eastward over the next 48 hours. According to the GFS from 0006 UTC, Madison's location on the southwestern fringe of the cyclone is responsible for the moderate, consistently northwesterly winds. Moving into Thursday evening, our area will no longer be severely impacted by said cyclone, but rather a weak anticyclone originating over Alberta, situated over the Great Plains. This anticyclone will be associated with clear conditions leading to the excessive nighttime heat loss, thus rationalizing the possible development of frost.

Our chances of precipitation Sunday come from the GFS analysis of 500mb, where Madison is situated upstream of a weak trough in geopotential height. Our case for vertical motion is further reinforced by a small region of positive vorticity at 500mb. Despite these conditions, we do not anticipate significant moisture in the air in order to produce precipitation. This comes from the forecasted cloudy conditions acting as a cap for convection.

Daniel Knuth
Rebecca Schultz

A Perfect Fall Week Ahead

Public weather briefing

Mild temperatures persist through the end of the work week. Skies will remain clear, with occasional clouds Wednesday night and Thursday. Highs will hover in the upper-50s. The weekend will be cooler, but still pleasant. Frost may occur just after dawn on Friday and Saturday. The best chance of rain will be seen Sunday night.

Forecast 

Tonight. Partly cloudy with skies clearing towards morning. Low around 37.

Wednesday. Clear skies through the day. Winds from the West around 10 mph. High around 59.

Wednesday night. Some clouds moving in. Low around 40.

Thursday. Mostly sunny skies. High around 58. Light winds from the Northwest. Low around 37.

Friday. Mostly sunny skies. Highs in the upper 50s. Lows in the upper 30s.

Outlook for the Weekend. Start of the weekend looks to have cool temperatures, falling into the mid-50s. Skies will be mostly sunny on Friday and Saturday. There is a possibility for frost in the early morning hours. Clouds on Sunday, with a chance of rain increasing into Sunday evening. [CONFIDENCE: MEDIUM]

Forecast Discussion

The surface cyclone centered over Western Ontario is experiencing favorable conditions allowing for further development. This cyclone will propagate eastward, leaving Madison under the influence of an area of high pressure. An anticyclone associated with the high-pressure system will approach Wisconsin, resulting in sunny skies and cooling temperatures for the remainder of the week.

Tropical Storm Simon will dissolve over northern Baja California, leaving moisture behind in the atmosphere.  This will be transported through the atmosphere via a combination of vertical motion, advection, and geostrophic wind.  The moisture will leave the atmosphere over the lower Midwest on Sunday, seen as a band of precipitation travelling to the southeast. 

Elizabeth Schenk
Lindsey Nytes

A Perfect Fall Week Ahead

Public weather briefing

Cold temperatures this past weekend have given way to warmer temperatures Monday afternoon. There is a very slight chance of precipitation in the early hours of Tuesday. The warm up will continue into Tuesday as winds from the West make their way into the area, creating a perfect fall day. Mild temperatures persist through the end of the work week, leading into a cooler, but pleasant weekend forecast. The best chance of rain will be seen Sunday night.

Forecast 

Tonight. Partly to mostly cloudy with a slight chance of showers. Low around 44.

Tuesday. Clearing skies, mostly sunny in the afternoon. Winds from the West at 10-15 mph. High around 62.

Tuesday night. Clear skies. Low around 38.

Wednesday. Sunny skies. High around 60. Light winds from the West. Low around 40.

Thursday. Mostly sunny skies. Highs in the upper 50s. Lows in the upper 30s.

Outlook for Friday through Sunday. Start of the weekend looks to have slightly cooler temperatures, falling into the upper-mid-50s. Skies will be mostly sunny on Friday and Saturday. There will be a possibility for frost in the early morning hours. Clouding over on Sunday, with a slight chance of rain towards the close of the weekend. [CONFIDENCE: MEDIUM]

Forecast Discussion

The surface cyclone centered over Western Ontario is experiencing favorable conditions allowing for continuous development. Precipitation from the rear of this cyclone is possible Monday night. This cyclone will propagate eastward, leaving Madison in the presence of an area of high pressure. A very linear band of precipitation propagates eastward, reaching the mid-Atlantic and northeastern states in the mid-morning hours of Tuesday. Tuesday will be the warmest day of the week in Madison, topping out in the low 60s. An anticyclone will approach Wisconsin resulting in sunny skies and cooling temperatures for the remainder of the work week.

Convergence aloft is seen to the west of surface convergence, showing a tilted nature. A jet seen at the 300 hPa level confirms convergence. The cyclone is expected to weaken mid-week, as the cold front intercepts the warm front, cutting off the warm air supply. This will merely be a disturbance by the end of the week. A pleasant weekend in on tap, with highs only reaching the upper 50s Friday, Saturday and Sunday. Temperatures will be below average ( average high 65F; low 40F).

Elizabeth Schenk
Lindsey Nytes

Frigid Weekend in the Mix

Public weather briefing

The dreary Thursday we are currently experiencing will continue into the night, with cooler temperatures arriving early in the morning Friday. Winds will shift to out of the northwest overnight, making for a cool, breezy Friday. Highs tomorrow will not make it out of the 50s, and Saturday will be even colder, with a high around 46. Temperatures Saturday morning will dip into the mid 30s, with a chance for some cold rain or even snow (!) early. Sunday will be drier and cold as well; we do not begin to warm up until early next week, with highs Monday still in the 50s and a possible high of 60 by Tuesday.

Forecast 

Tonight. Quite rainy. Over half an inch of rain is possible. Low of 53.

Friday. Some lingering rain showers, especially in the morning. High of 54. Very windy; winds around 15 mph, gusting as high as 30 mph.

Friday night. Possible showers late. Cold. Low around 35. Windy conditions continue.

Saturday. Coldest day of the week. High around 46.

Sunday. Possible return of sun, but still mostly cloudy. Winds die down in the morning. High of 53.

Outlook for Monday through Wednesday. First part of next week looks to remain cool, with temps remaining in the mid-50s. Will be much clearer and drier than the weekend. Lows at night typically in the low 40s. Fall has arrived. 

Forecast Discussion

The cold front initiated by the low in southern Canada comes through later tonight, roughly around midnight. We will see widespread precipitation throughout tonight and early Friday morning. This precipitation was initially generated from convection in Missouri, and enhanced by a deep trough aloft. This deep trough exhibited significant PVA by the thermal wind over much of the central plains, further driving upward vertical motion. The genesis of the remaining precipitation was from the cold front, so we will likely see an end to the heaviest rain after midnight tonight. 

The very northerly flow on the other side of this front will bring cold temperatures for Saturday and much of the weekend, with the possibility for snow early Saturday morning. The MOS puts this probability at around 66 percent as of the 18Z forecast, but this is only if the atmosphere is precipitating. The flow over our area remains westerly/northwesterly through much of the weekend and early next week. Conditions will be much drier by Sunday, and continue through the early week, due to a surface low which will remain just north of the forecast area for several days.

Alex Haugstad
Conner Hardesty

Moist and Cool Days Ahead

Public weather briefing

We knew that the nice weather wouldn't last forever, and the upcoming days are a clear indicator of that fact. Thursday brings rain for most of the day and a chance for thunderstorms in the afternoon. Around midnight on Thursday night/Friday morning, the winds will shift from southerly to out of the northwest. There will still be a chance for showers on Friday, but leading into the weekend, dryer and cooler conditions will prevail. Following the weekend, temperatures will warm up slightly but won't reach the arguably unseasonable temperatures of late.

Forecast 

Tonight.  Slight chance of t-storm and showers through the night, temps in the low 60s

Thursday. Showers and thunderstorms likely. High around 72.

Thursday night. More showers.  Low in the 50's.

Friday. Chances for showers continue. Winds shift to NW through early morning. Winds 10-15 mph, with gusts as high as 25 mph. High of 56, low of 37.

Saturday. Much cooler and drier. Partly cloudy with a high of 48, low of 35

Outlook for Sunday through Tuesday. Another cooler day Sunday, with highs in the low 50s under partly cloudy skies. Much clearer days early into next week, with temperatures warming up slightly into the upper 50s on Monday and low 60s by Tuesday. [CONFIDENCE: MEDIUM]

Forecast Discussion

The current pattern of warm air advection over our area will change drastically over the next 24 hours, as a moderate cyclone currently centered over central Manitoba moves eastward, bringing a significant cold front through late Thursday night around midnight, with winds shifting from generally southerly to out of the northwest. Cold air advection will prevail after the front moves through, with a surge of Canadian air southward during the day Friday and into the weekend. Cloudy skies on Friday will further prevent temperatures from rebounding during the day, making for a cool, potentially rainy day Friday. 

Conditions will dry out considerably into the weekend, due to the cool, dry air being advected southward, with colder air lingering through most of the weekend. Precipitation will mainly be limited to during the day Thursday and into Thursday night and Friday morning. The GFS 700mb vertical motion in combination with the surface precipitation map indicates that the maximum precipitation will occur more along the Wisconsin-Minnesota border and progress northeastward, as the surface low moves into northern Canada. Therefore, the rain we see Thursday into Friday will likely be less significant than west of the forecast area. Next week appears to warm up, as the cold air advection subsides, with winds generally out of the west.

 

Alex Haugstad
Conner Hardesty