Rain likely, Snow??

Public weather briefing

After a much cooler day, clouds will remain in the area as lows will again drop into the 40s. Overnight winds will remain light and become slightly more southeasterly. Highs tomorrow will be much more comfortable and will continue this warming trend into Thursday with highs around 70. The warmth will bring a chance for rain overnight on Wednesday and increases in probability through Thursday. Winds will remain out of the south through Thursday. Friday will bring the highest chance for showers. Winds will be stronger and out of the west and highs will reach into the 50s. There will be a big cool down over the weekend especially on Saturday and a small chance for showers through Monday. 

Forecast 

Tonight. Partly cloudy. Low around 45. Light east winds becoming southeast around 5 mph.

Wednesday. Mostly cloudy a slight chance of showers after 4 pm. High around 67. Southeast winds 5 to 10 mph. Chance of rain 20%.

Wednesday night. Showers becoming likely mainly after midnight. Lows in the upper 50s. Light south winds. Chance of rain 70%.

Thursday.  Showers likely mainly before 1 pm. Highs around 70. Light south winds. Chance of rain 70%.

Friday. Showers likely early, then breezy and cooler. Highs in the mid 50s. West wind 10-20 mph. Chance of rain 80%.

Outlook for Saturday through Monday. Much cooler Saturday, but partly cloudy with highs in the low to mid 50s. Partly cloudy Sunday with a small chance of light showers and highs in the mid to upper 50s. Monday partly cloudy with highs in the upper 50s. [CONFIDENCE: MEDIUM]

Forecast Discussion

Look for a quiet night as the surface anticyclone remains in control through the night. Temperatures should stay right around where they are for the remainder of the night as WAA begins aloft.
Wednesday through Thursday: big difference in placement of features with the approaching upper level through to the west. There will be a small chance of showers Wednesday afternoon, becoming likely Wednesday night into Thursday as upper divergence and areas of vertical upward motion approach the area. The GFS has almost no rain overnight Wednesday into Thursday, while the NAM puts around an inch during the same time. Any sun on Thursday will boost temperatures at or above 70F. 
Thursday night: Upper trough axis approaches the area with decent upward vertical motion. Showers could get moderate to heavy overnight. Very little instability seen on soundings so no mention of thunder at this time. 
Friday and beyond: Surface cyclone moves northeast of the area drying things out and cooling things down quickly by midday Friday. Interestingly, both models are in good agreement with an area of wrap around moisture coming through overnight Friday into Saturday. Could be some snow flakes mixing in at times as the 5400 m thickness line is well south and southeast of the area. GFS has 850 mb temps well below 0C and 925 mb temps around 0C. Otherwise a weak shortwave within the northwest upper flow could bring a small chance of showers Sunday with continued cool conditions.   

Ross Braatz
Ryan Tvedt

It's Going to be a Troughy Week

Public weather briefing

After a near perfect and mild weekend, Monday started off continuing this trend as the morning temperatures were again above average and there were mostly sunny skies. Temperatures for this afternoon are expected to stay well above normal. Clouds are expected to move in this afternoon that may bring a slight chance of rain for this evening followed by a much cooler Tuesday with mostly sunny skies. chances of rain and possibly thunderstorms increase into Wednesday through early Friday. A much cooler weekend is in store with highs only in the 50s on Saturday and highs in the low 60s on Sunday.

Forecast 

Tonight. Slight chance of showers early, mainly before 7pm then cloudy and cooler with lows around 44. Northeast winds 5-10mph.

Tuesday. Mostly Sunny and cooler with a highs around 62. East winds around 5mph.

Tuesday night. Partly cloudy. Lows around 46 with light southeast winds.

Wednesday. Mostly cloudy. A 30% chance of showers after 1pm. Highs around 70 and southeast winds 5-10mph. 

Thursday. Showers and thunderstorms likely. Southwest winds 5-10mph. Highs around 74. Chance of rain 60%.

Outlook for Friday through Sunday. Showers ending early Friday turning cooler and breezy Friday with highs in the low 60s. Sunny Saturday with highs in the mid 50s. Partly cloudy Sunday with highs in the low 60s. [CONFIDENCE: MEDIUM-HIGH]

Forecast Discussion

Shortwave trough with associated vorticity maximum swinging southeast through the central Great Lakes region will drag a cold front and a weak 850 mb front through the region early in the period. Weak to moderate 850-700 mb negative omega associated with right jet entrance region of upper jet streak will result in at least a chance of SHRA as well. Very little instability is seen so no mention of thunder. Omega wanes quickly after 00Z and drying at 850mb will bring an end to any showers. Expect temperatures to drop to the mid 50s by mid evening. Low stratus deck should overtake the area. Weak high pressure on Tuesday will bring a sunny but cooler day as 850 mb temperatures drop to around 8 degrees Celsius. Cool east winds will result in temperatures in the low to mid 60s. Low level WAA quickly occurs in the wake of departing high as longwave trough approaches from the west.

Wednesday through Thursday night there is upper flow that becomes southwest as upper ridge moves off to the east during the day Wednesday. Upper jet increases over Minnesota and puts southern Wisconsin in an area of upper divergence resulting in upward vertical motion after 21Z on Wednesday. GFS quite a bit weaker with upward motion and vorticity advection. Small chances of rain seem reasonable with the bulk to our Northwest. Meanwhile upper jet strengthens to the west Wednesday night through Thursday night which results in upward vertical motion with embedded vorticity maximums through the period. Will put likely wording for rain/storms after midnight Wednesday night through at least early Thursday. NAM dries things out Thursday while GFS keeps precipitation in area through early Friday morning.

Early rain on Friday will give  way to cooler and dryer conditions with 1000-500 mb thickness dropping to about 5420 meters. Much cooler weather is forecast for Saturday under mostly sunny skies. An embedded vorticity maximum may bring light showers overnight Saturday into Sunday.

Ryan Tvedt
Ross Braatz

Sunny and Clear Conditions Continue with the Uncertainty of Precipitation Early Next Week

Public weather briefing

Clear skies for the rest of the week into the weekend will persist. Light wind from the south/southeast will also continue until Monday where we will see a westerly shift in wind. Monday night will likely have mostly cloudy skies along with a chance of precipitation during the later hours.  The cloud cover is expected to dissipate early Tuesday with mostly sunny skies dominating for the rest of the day. Highs into the weekend and early next week will be in the upper 70’s with lows in the lower 50’s, giving a consistent stretch of weather through early next week.  

Forecast 

Tonight. Mostly clear skies with patches of fog. Calm wind. Low around 48.

Friday. Sunny with light wind.  High around 78.

Friday night. Clear with light wind. Low near 53.

Saturday. Sunny with light wind.  Highs in the upper 70s.  Lows in the lower 50s

Sunday. Continued clear and sunny with light wind. Highs in the upper 70s.  Lows in the lower 50s.

Outlook for Monday through Tuesday. Mostly sunny on Monday with light wind and a chance of light showers overnight. High in the mid 70’s and low in the lower 50’s.  Mostly sunny Tuesday with encroaching clouds overnight. Highs in the lower 70s and lows in the lower 50s. [CONFIDENCE: HIGH]

Forecast Discussion

The dry air in our region, along with the dissipating trough over Lake Superior, caused the clouds to break up much earlier than predicted during the day Thursday.  Clearing skies further promoted surface heating, which caused the daytime high to be slightly higher than originally forecasted for the day.

For the rest of the week and into the weekend our weather will be primarily dominated by the anticyclone over the eastern Great Lakes region, bringing southerly winds as well as warm air and clear skies. The GSF projects the formation of a weak area of low-pressure over northern Wisconsin early Monday.  This will bring weak westerly winds along with a slight chance of precipitation as an area of baroclinicity also moves down from the north. Northern Wisconsin is likely to receive light rain fall but there is some uncertainty as to the possibility of precipitation for southern Wisconsin as the dry air that will be covering the region for the next few days may be enough to impede any rainfall. The southern half of the state will likely experience mostly cloudy conditions Monday night along with a 20% chance of rain. 

Westerly winds will persist into Tuesday possibly bringing cloudy conditions in association with another cyclone projected to move east over the northern plains states bringing more moist air and an area of upper level divergence producing upward vertical motion in the Wisconsin/Iowa region.

Craig Oswald and Cody Kuchinski

Sunny and Clear Conditions Followed by Possible Rain Next Week

Public weather briefing

The passing cloud cover associated with the precipitation to our west will move north/northeast out of the area by Thursday night providing mostly clear and sunny skies for Friday and the weekend.  Light southerly/southwesterly winds will continue to bring comfortable temperatures in the mid to upper 70s to the region through the rest of the week and into the weekend.  Lows are expected to be in the mid to lower 50s providing the outlook for an excellent September weekend which will persist into Monday morning.  Mostly sunny skies will persist through the day on Monday with light showers possibly moving over Madison and the surrounding areas during the night.

Forecast 

Tonight. Mostly cloudy with light wind. Low around 54.

Thursday. Partly cloudy with light wind.  High around 73.

Thursday night. Clearing skies and light wind. Low near 53.

Friday. Sunny with light wind.  Highs in the upper 70s.  Lows in the lower 50s

Saturday. Continued clear and sunny with light wind. Highs in the upper 70s.  Lows in the lower 50s.

Outlook for Sunday through Monday. Mostly sunny on Sunday with light wind.  Mostly sunny Monday with the chance of a light shower during the overnight.  Highs in the upper 70s Sunday and mid-70s Monday. Lows in the 50's. [CONFIDENCE: HIGH]

Forecast Discussion

The rain showers associated with an area of upper level divergence over Minnesota/Iowa are expected to die out before they reach southern Wisconsin due to a layer of dry air covering the region as well as dissipation of the upper level trough as it moves northeast.  The remaining moisture will provide scattered cloud cover through most of the day Thursday.

An anticyclone centered over Lakes Erie and Ontario will persist through the weekend and continue to advect warm, dry air from the south/southwest. As a result, mostly clear skies will persist producing cooler night time temperatures.  The anticyclone is projected by the GFS to move out of the eastern great lakes region Sunday night as a weak cyclone develops over western Ontario. With support by an upper level trough, the cyclone is projected to move along the eastern border of the Great Lakes through Monday.  This cyclone, accompanied by an area of modest baroclinicity moving into Wisconsin from the north, poses a threat of light rain Monday night. 

Craig Oswald and Cody Kuchinski

Continued Sunny Weather for the Rest of the Week

Public weather briefing

After a very nice Monday, the great weather continues for most of the week. Warm temperatures will be continue throughout the week.  Temperatures will stay in the low 70's for the middle of the week and rise to the mid to high 70's for the end of the week and start of the weekend.  Lows will be in the low to mid 50's throughout the week as well.  It should be, for the most part, a clear and sunny week due to the high pressure system located over the area.  However, with a system to the west-southwest, the outlook for rain is now possible for Wednesday night into Thursday morning's forecast.  Along with early morning fog for the middle of the week, these should be the only threats to what should be an overall excellent week and weekend outlook.

Forecast 

Tonight. Clear skies with light wind from the south. Low around 50.

Wednesday. Clear morning with clouds increasing throughout the day becoming mostly cloudy. Possibility of showers in the evening.  High around 70.

Wednesday night. Cloudy with light southerly winds.  Lows in the lower 50's. Chance of showers into Thursday morning.

Thursday. Chance of showers in the early morning. Continued cloudiness throughout the morning and into the afternoon.  Calm winds.  High in the mid to low 70's.  Low around 50. 

Friday. Clear conditions and warm temperatures.  High in the mid 70's.  Low in the low 50's.  Chance of patchy fog in the early morning.

Outlook for Saturday through Monday. Mostly sunny all weekend into the early week. Temperature highs in the low to mid 70's with lows in the 50's throughout the weekend. [CONFIDENCE: MEDIUM-HIGH]

Forecast Discussion

The high pressure anticyclone continues to stay in the eastern midwest crawling further east.  It will continue to bring warm air advection, which will be felt later in the week.  Currently, the state of Wisconsin in under a very large high pressure ridge stretching into Canada creating very nice conditions for the area.

Temperatures will continue to slowly rise throughout the week, going from the low 70's in the middle of the week to the mid to high 70's later in the week.  This is due to the warm air advection coming from the south carried north to the upper midwest region.  Low's will be consistently in low 50's bringing on the chance of condensation at the low levels of the atmosphere.  This could pose a threat for fog into Friday morning's forecast. 

Yesterday's forecast showed a low pressure trough that looked to be dying out before reaching the Madison area.  However, models now show that this system will continue to move northeast into the area giving the chance for precipitation in the central and northern regions of Wisconsin stretching into Madison for Wednesday night and into Thursday morning before finally dying out shortly after.  This is due to the severe curvature of the cyclone in Minnesota-South Dakota-Iowa region creating divergence in the upper atmosphere to the east causing lifting, which leads to precipitation in this western region.

Will Hahn and Andrew Goenner

Clear Skies and Fantastic Weather for the Week

Public weather briefing

After a rainy Saturday associated with a cold front moving through the area, pleasant conditions have taken over the city.  Sunny skies and warm temperatures will be apparent throughout the week.  Temperatures will start in the low 70's early in the week and steadily rise to the mid to high 70's for the start of the weekend.  Lows will be in the low to mid 50's throughout the week as well.  It should be a clear and sunny week due to the high pressure system located over the area and other than the chance for some fog in the mornings it should be a very nice week overall.  

Forecast 

Tonight. Clear skies with light westerly winds. Lows in the mid to high 40's.

Tuesday. Mostly sunny with calm winds. High around 70.

Tuesday night. Clear and calm.  Lows in the lower 50's. 

Wednesday. Mostly sunny and warmer. Light southerly winds. High in the mid to low 70's. Low around 50. Chance of patchy fog in the early morning.

Thursday. More sun and continued warm temps. High in the mid 70's.  Low in the low 50's.

Outlook for Friday through Sunday. Mostly sunny all weekend. Temperature highs in the low to mid 70's with lows in the 50's throughout the weekend. [CONFIDENCE: HIGH]

Forecast Discussion

The arrival of an anticyclone over the weekend has brought warm temperatures and clear skies.  This anticyclone came from the southwest and has brought with it warm air advection.  These conditions will continue throughout the week as this anticyclone will slowly crawl eastward due the lack of any cyclones moving through the area from the west.  There is also large ridge over mid-central Canada so there is no interaction from the jet that could push this through for the foreseeable future.  

Temperatures will be consistently warm in the low to mid 70's throughout the week.  It will steadily rise a few degrees as the week progress from the warm air advection pushing its way north from the south.  With the clear skies and light winds occurring during the night, temperatures will drop down near the dew points posing the threat for fog in the mornings for this week.  According to the models, the next chance of rain appears to be early to mid next week from a cyclone that hasn't made landfall yet in the north Pacific.

Will Hahn and Andrew Goenner

A perfect Friday followed by an unsettled Saturday

Public weather briefing

Cool conditions on Thursday are not expected to last long, as winds will become southerly overnight tonight, ushering in warmer air and temperatures in the 70's for Friday. The passage of a warm front on Friday night will set up a warm and humid Saturday with temperatures in the mid-70's. Along with these more humid conditions comes a chance of scattered showers and thunderstorms. Rain chances appear to be the highest prior to kickoff, so it might be wise to bring a tent and poncho to your tailgate, and taper off into the afternoon. A cold front sweeps through Saturday evening, setting up an absolutely perfect stretch of September weather for southern Wisconsin through the middle of next week.

Forecast 

Tonight. Becoming partly cloudy. Light easterly winds turning southerly towards morning. Lows around 50.

Friday. Mostly sunny and breezy. Southerly winds 10-20 mph. Highs in the low 70's

Friday night. Increasing clouds with a chance of scattered showers and thunderstorms towards dawn. Southerly winds 7-15 mph. Lows in the lower 60's.

Saturday. Scattered showers and thunderstorms during the morning, with chances tapering off during the afternoon. Warm and Humid with highs in the mid 70's and lows in the upper 50's. Rainfall accumulations on the order of a half an inch with locally higher amounts in thunderstorms.

Sunday. Mostly sunny and less humid. Highs around 70.

Outlook for Monday through Wednesday. Sunny skies and pleasant. Highs in the mid-60's on Monday, increasing to near 70 by Wednesday. Lows in the mid-40's. [CONFIDENCE: HIGH]

Forecast Discussion

Winds are expected to become southerly overnight as the Canadian anticyclone over our area shifts further eastward, encouraging the return of higher thicknesses over the area on Friday. A warm front approaches southern Wisconsin on Friday night, bringing a chance of scattered showers and thunderstorms by early Saturday morning at the nose of a strong low-level jet. At the moment, it appears that rain chances will taper off during the afternoon. However, a forecast challenge surrounds the speed of the cold front expected to pass through Saturday evening. Current model forecasts show the front passing through before a renewed round of precipitation develops in response to low-level frontogenesis along the boundary. If the front slows down, southern Wisconsin may experience extended chances of showers and thunderstorms into the afternoon and early evening hours.

By Sunday, an upper-level ridge and Canadian anticyclone settle into the area, setting up the beginning of an absolutely perfect stretch of late-September weather. General subsidence and the dry air mass in place are expected to keep skies clear for the early part of the week, helping to warm temperatures into the mid-60's during the day and cooling off into the mid-40's overnight.

Andrew C. Winters

A cool Thursday expected with warm and humid conditions arriving for the first half of the weekend.

Public weather briefing

Following an absolutely brilliant Wednesday, the passage of a "backdoor" cold front ushers in cloudier and cooler conditions for Thursday. Skies are expected to clear out overnight on Thursday, setting up a rather seasonable Friday with clear skies and temperatures around 70. The passage of a warm front on Friday night brings a chance of scattered thunderstorms towards dawn and may damper some of the early morning tailgates, as rather warm and humid conditions move in for Badger Gameday. The passage of a cold front brings a renewed chance of thunderstorms Saturday afternoon and evening before more crisp, autumnal weather returns for the second half of the weekend and early next week.

Forecast 

Tonight. Clear with increasing clouds towards morning. Light winds. Lows in the upper-40's.

Thursday. Partly sunny. Light ENE winds 5-10 mph. Highs around 65.

Thursday night. Clearing overnight. Light southerly winds. Lows around 50.

Friday. Sunny and warmer with a chance of scattered thunderstorms after midnight. Southerly winds around 10mph. Highs in the low-70's. Lows around 60.

Saturday. Mostly sunny and more humid with a chance of scattered thunderstorms. Breezy. Highs in the upper 70's.

Outlook for Sunday through Tuesday. Clearing Sunday morning with mostly sunny skies Sunday afternoon through Tuesday. Highs in the mid-to-upper 60's and lows in the 40's. [CONFIDENCE: MEDIUM]

Forecast Discussion

Subsidence accompanying a Canadian anticyclone settles in over the area early this evening, bringing light winds to southern Wisconsin. The approach of a backdoor cold front appears to be associated with subtle ascent over southern Wisconsin, promoting increasing clouds towards morning and a cooler Thursday, though no precipitation given the relatively dry air mass in place. A forecast challenge surrounds how far this "backdoor" cold front is expected to move inland and the degree of cloud cover expected. Less cloud coverage and a less progressive front may encourage warmer temperatures than currently forecast.

Strong warm-air advection from the southwest, as the Canadian anticyclone shifts eastward, ushers in warmer temperatures on Friday. Maximized areas of warm-air advection during the overnight hours on Friday, encouraged at the nose of a strong low-level jet, may support the development of a few scattered thunderstorms towards morning. Conditions will be more humid and warmer on Saturday in advance of a strong cold frontal boundary that will move through the area on Saturday evening. Deformation along the frontal boundary suggests a region of low-level frontogenesis and the development of precipitation along the length of the boundary Saturday afternoon and evening across the state. Lifted indices appear to be favorable for convection to occur. Following the passage of the front, another Canadian anticyclone settles into the area from the north, ushering the return of more autumnal weather.

Andrew C. Winters

Warm Wednesday, cooler Thursday, then an even warmer week's end . . .

Public weather briefing

The last of our unseasonable cool night will occur this evening as clear skies and light winds provide favorable conditions for cooling off. Tomorrow will be mostly sunny and warmer than today as westerly winds transport warmer air into the southern Wisconsin. Thursday, a shift in winds from the north and east will herald the arrival  of cooler temperatures and some low clouds before westerly winds resume and warm air from the south and west transports in warmer temperatures. Rain showers are expected late Saturday before temperatures dip to below seasonal normals on Monday.

Forecast 

Tonight. Clear with light  winds. Lows around 40.

Wednesday. Mostly sunny with light winds. High around 69.

Wednesday night. Partly cloudy.  Winds become easterly by dawn on Thursday. Low in the mid 40's.

Thursday. Mostly cloudy and cooler. Clearing late. Winds east 5-9 mph. High near 60. Low upper 40's.

Friday. Sunny. High near 68.

Outlook for Saturday through Monday. Partly cloudy Saturday with rain and rain showers in the afternoon and night; clearing, breezy and cooler Sunday.  Highs in the upper 70's Saturday and low 70's Sunday and upper 60's Monday. Lows in the upper 50's to lower 60's Saturday and Sunday morning and in the lower to mid 50's on Monday. [CONFIDENCE: MEDIUM]

Forecast Discussion

With full sun, the high temperatures on Wednesday will easily rebound into the upper 60's.  The passage of a weak but dry front late Wednesday will keep temperatures cooler over the state as another anticyclone builds west and south over the area from southern Canada. As the anticyclone moves east on Friday, warm thickness advection will boost temperatures up to and beyond daily normals for the week's end (average daily high temperature for later in the week 70F; low 49F).

The only wrinkle in an otherwise dry forecast for the week, is the overall fate of Tropical Storm Odile located on Tuesday late afternoon over the central Baja Peninsula of Mexico.  The remnants of the cyclone (primarily the water vapor) are forecast by the GFS to move into the southwestern US and then northeast to the midwest by week's end. If this moisture gets entrained into the broad southwesterly flow ahead of a cyclone moving through northern Wisconsin on Saturday, a wet Saturday afternoon and evening is possible for southern Wisconsin. Clearing conditions will follow in the cyclone's wake on Sunday. After a brief period of cold advection Sunday, warm advection returns Monday afternoon before another Canadian anticyclones builds into the state.

Michael C. Morgan

Seasonable weather returns

Public weather briefing

After a chilly weekend and a "drizmal" (drizzly+dismal) Monday morning and early afternoon, clearing conditions and milder afternoon temperatures are anticipated for the week ahead.  The rainfall from this morning and early-to-mid afternoon will end in southeastern WI this evening and skies will clear from west to east.  Low temperatures tonight and tomorrow will be a bit below normal but will moderate later this week.  Daytime high temperatures will slowly increase this week with mostly sunny skies.  Rain and rain showers are possible on Saturday.

Forecast 

Tonight. Clearing with light northerly winds. Lows in the upper 30's.

Tuesday. Mostly sunny with light winds. High around 65.

Tuesday night. Clear and cool.  Low in the lower 40's.

Wednesday. Sunny and warmer. Light winds. High 68. Low around 45.

Thursday. Continued sunny. High near 70.

Outlook for Friday through Sunday. Partly cloudy Friday, rain and rain showers Saturday, clearing Sunday.  Highs in the mid 70's Friday and around 70 Saturday and Sunday. Lows in the 50's.

Forecast Discussion

Subsidence accompanying the arrival of an anticyclone over the upper-midwest this evening will provide clearing skies.  With light winds and clear skies, radiational cooling will be maximized leading to chilly nights tonight and Tuesday.  With full sun, the high temperatures on Tuesday will easily rebound into the mid 60's.  A weak but dry frontal passage on Wednesday afternoon will slow the warm-up over the state as another anticyclone builds over the area from southern Canada. As the anticyclone moves east, warm thickness advection will boost temperatures up to and beyond daily normals for the week's end (average daily high temperature for later in the week 70F; low 49F).

The only wrinkle in an otherwise dry forecast for the week, is the overall fate of Hurricane Odile located over the southern Baja Peninsula of Mexico.  The remnants of the cyclone (primarily the water vapor) are forecast by the GFS to move into the southwestern US and then northeast to the midwest by weeks end. If this moisture gets entrained into the broad southwesterly flow expected to develop over the central US, a wet Saturday is possible for southern Wisconsin.

Michael C. Morgan