Thursday, October 22, 2015

Rain to "turn up" on Friday night

Public weather briefing

After a clear, dry day today, clouds will move in overnight and persist throughout Friday, followed by steady rainfall starting in the evening and continuing through till Saturday late morning. Sunday will see a return to clear, sunny and mild conditions. Into next week temperatures will remain around the 60 mark before a drop in temperature on Wednesday, along with high chances of rainfall.

Forecast 

Tonight. Partly cloudy. Low around 42.

Friday. Cloudy and moderate winds during the day, followed by persistent rainfall beginning in the afternoon, providing around a quarter of an inch by the end of the day. Winds will be moderate, with strong gusts. High around 56.

Friday night. Continued rainfall. Temperatures will increase overnight, around 60.

Saturday. Rainfall set to continue until late morning, with cloudy skies later on. Highs around 60, lows in the low 40s.

Sunday. Abundant sunshine. Highs in the low 60s and lows in the low 40s.

Outlook for Monday through Wednesday. Monday and Tuesday will be partly cloudy, with outbreaks of sunshine and highs in the upper 50s and lows in the mid 40s. By Wednesday temperatures drop, with highs in the low 50s. Showers are likely throughout the day.  [CONFIDENCE: MEDIUM]

Forecast Discussion

High pressure to the north-east will continue to bring quiet weather over night tonight. A low pressure system moving up from the central plains towards the Midwest will cause differential warm air advection over us into Friday morning.  Tightening of the pressure gradient will allow for gusty southeast winds in the afternoon.  By the evening we are located downstream of a short-wave trough and in the left jet exit region of a small jet streak, both of which will act to strengthen the low pressure and provide increased upward vertical motion due to upper level divergence over Wisconsin, bringing steady rainfall, which will last into the night. Q-vector convergence over Madison on Saturday morning suggests continued strong upward vertical motion, forcing precipitation to persist. This rainfall should end around midday and by the evening, high pressure will be overhead, which will remain through Sunday night and into Monday. Tuesday and Wednesday will see precipitation chances high again, as a deep mid level trough along with a surface low moves across the region. Wednesday onwards is likely to see differential cold air advection, as a result of deep low pressure systems off the west coast of the US moving east, resulting in much cooler temperatures.

Rich Johnson

Wednesday, October 21, 2015

Bring an Umbrella Friday Night

Public weather briefing

Following a few light showers today, the evening is expected to be clear.  Gradual cooling will occur over the next few days into the weekend.  A clear day is expected for tomorrow followed by a high likelihood of rain beginning on Friday evening and continuing into Saturday morning.  Temperatures will be around 60 this weekend with partly cloudy skies until Sunday night when there is a chance of rain.  Temperatures will remain moderate into next week.  

Forecast 

Tonight. A few clouds. Low around 43.

Thursday. Mostly clear. High around 64.

Thursday night.  Partly cloudy.  Lows in the low 40s.

Friday. Cloudy with rain beginning in the evening. Moderate winds. Highs around 60 and lows in the upper 50s.

Saturday. Rain into the morning with cloudy skies later in the day.  High of around 58.  Lows around 40.  

Outlook for Sunday through Tuesday. For Sunday through Tuesday Highs should be about 60 with lows in the evening of around 45. A slight chance of rain exists Sunday night followed by a cloudy Monday and a chance of scattered thunderstorms Tuesday.  [CONFIDENCE: MEDIUM]

Forecast Discussion

A cold front associated with a low centered over Ontario will pass through the region this evening with cool and dry air following in behind.  The dry air will reduce clouds into the night and Thursday Morning.  Skies will be partly cloudy on Thursday.  Then, a Colorado Low moving through the plains will reach southwestern Minnesota by Friday afternoon, forcing differential warm air advection to the east of its center. At this time, showers may begin.  A short wave trough will provide the means to lift the warm and moist air with its downstream, upper level divergence located above Wisconsin.  In addition, modeling of Q-Vector convergence indicates strong upward vertical motion that will also aid in the production of precipitation into Saturday morning.  Subsidence and more dry air following the event will make for a calm Saturday and Sunday.  


Alexander F. Fox

Monday, October 19, 2015

Warm Weather Transitioning to Average

Public weather briefing

Seasonably warm weather with temperatures 10 to 15 degrees above average will continue to hang around Tuesday and Wednesday, but a cold front associated with a weak low pressure system in northern Minnesota will put a damper to our summer-like temperatures with showers and maybe a few rumbles of thunder as it moves through on Wednesday afternoon. A Canadian high pressure system over Ontario influencing our weather will result in a drier, sunny, and more seasonably-average temperatures for Thursday. A weak low pressure system will track through Wisconsin from the Plains on Friday night and Saturday, bringing a likely chance of showers. This system moves out early Sunday as a high pressure system builds in from the Plains, leading to a dry Sunday.

Forecast 

Tonight. Partly cloudy, with a low near 54. Southwest winds at 10 to 15 mph.

Tuesday. Mostly sunny with a slight chance of showers late afternoon and into the evening. High around 72. Southwest winds around 10 mph.

Tuesday night. Mostly cloudy with a moderate chance of showers and a low near 53. Light southerly winds at 5 mph.

Wednesday. Partly cloudy with a slight chance of showers during the day and clouds clearing overnight. High near 67, with a low around 41. Winds 10 to 20 mph during the day shifting from the south to the northwest.

Thursday. Sunny and cooler, with a high around 60 and a low near 40.

Outlook for Friday through Sunday. Showers likely Friday night, otherwise mostly cloudy during the day with a high near 59 and a low around 51. Showers again are possible Saturday, transitioning to clear skies for Saturday night and Sunday. For Saturday and Sunday, highs will be in the mid to upper 50's and lows will be in the upper 30's.  [CONFIDENCE: MEDIUM]

Forecast Discussion

A weak shortwave trough moving into Wisconsin from Minnesota brings a chance of rain Tuesday afternoon and evening. This will be followed by a surface cold front associated with an upper level trough in southwestern Ontario and southern Manitoba. Soundings reveal an environment with a few hundred joules of CAPE, meaning some weak convection may be possible as this cold front passes through our region. Still, the highest differential vorticity advection and Q-vector convergence is to our north in northern Wisconsin. Height rises follow as the low pressure system over southern Ontario tracks northeastward on Thursday and ridging builds into our region. A weak lee-side trough forms on the Rockies and slides into our region Friday night into Saturday with a very disorganized vorticity field, although it will still produce some measurable precipitation. High pressure from the plains will bring quiet weather to Madison for Sunday.

Robert Kelnosky

Wednesday, October 14, 2015

Midterms: Not the Only Source of High Pressure

Public weather briefing

This week is set up to end exactly the way it started: with clear, sunny skies and temperatures consistently ranging from 30 to 60 degrees Fahrenheit. No precipitation is expected until Tuesday at the earliest. Maximum wind speeds this week are expected to be around 15 mph. Friday and Saturday will be the coolest days this week (and not just because of the start of the weekend!) with highs of 50, so wear a light sweater.

Forecast 

Tonight. Clear Skies with no precipitation. Lows in the mid 40s.Thursday. Partly cloudy with light winds. High in the upper 60s..\Thursday night. Partly cloudy with winds of or under 10 mph.Friday. Sunny, but cool. High of 50 and a low of 30. Winds during the day around 10 mph.
Saturday. Clear and cool. High of 50 and low of 30.
Outlook for Sunday through Tuesday. 
Sunday and Monday will be very similar to Friday and Saturday, as Madison will continue to be sunny with light winds. Sunday and Monday will get progressively warmer, with respective highs of 60 and 65 and respective lows of 40 and 50. 30% chance of rain on Tuesday with a high of 70 and low of 50.  [CONFIDENCE: MEDIUM]

Forecast Discussion

Much of the western United States lies just south of a significant ridge. This is creating a bubble of high pressure moving west to east that is expected to go envelop Wisconsin over the last few days of the week, hence the lack of precipitation and any significant cyclonic action. The change in along-flow wind speed at all levels (particularly at 300 mb) is relatively low, meaning this feature is not expected to gain substantial energy. Any precipitation or cool air next week is instead expected to come from cool Canadian air pushed southward by cyclonic activity off the Gulf of Alaska.
Conversely, the American Northeast is enveloped in a minor cyclone, which is likely to have precipitative consequences for our wxchallenge forecasting results! Keep an eye out!


Corinne Trott

Tuesday, October 13, 2015

Small Rollercoaster Ahead (and frost!!!)

Public weather briefing

After a nice cold frontal passage and winds gusting over 40 mph yesterday, cool air surged in from the northwest for a cool Tuesday. Tonight the coolness will persist as clouds move out during the evening, leading to a clear and cold night. However, expect a warm up for Wednesday and Thursday as a high pressure system tracks from the Northern Plains into the Midwest, bringing warmer and drier air into our region. Another low pressure system and its associated cold front will move through Thursday morning. A high pressure system sliding in from Canada will lead to clearing as well as our first two autumnal frosts both Friday and Saturday overnight. Yet again, our cool weather will be transient, with a warm up expected Sunday as a warm front associated with a low pressure system over northern Manitoba passes through the region.

Forecast 

Tonight. Clouds clearing this evening. Cold. Low 38. Light winds northwest decreasing from 10 to 5 mph.

Wednesday. Sunny and warmer, with a high around 65. Winds west at 10 to 15 mph.

Wednesday night. Mostly clear and cool. Low near 43. Light winds from the northwest at 5 to 10 mph.

Thursday. Showers possible early morning. Mostly sunny and cooler. High of 58 and a low near 35. Northwest winds increasing from 10 to 15 mph to 15 to 20 mph during the afternoon.

Friday. Sunny yet cool during the day. Clear and cold with widespread frost overnight. High near 49 with a low around 27. Northwest winds at 5 to 15 mph.

Outlook for Saturday through Sunday. Widespread frost Saturday morning and again Saturday overnight. Sunny skies and a clearing overnight, with highs around 50 and lows in the upper 20's. For Sunday, frost will linger into morning, with sunny skies and highs in the mid-50's and lows overnight in the lower 40's. Southerly winds will increase from 15 to 20 mph during the day, to 20 to 25 mph overnight. [CONFIDENCE: MEDIUM]

Forecast Discussion

A high pressure system associated with strong zonal flow will move from the Northern Plains into the Midwest, leading to drier and warmer air over the region due to the air mass originating from subsidence down the lee-side of the Rockies. Early Thursday morning, positive advection of vorticity at 500mb by the thermal wind associated with a shortwave trough over Wisconsin will lead to upward vertical motion across southern Wisconsin. This shortwave is associated with a low pressure system in northern Manitoba The return of moisture to the low levels of the atmosphere will be vital regarding whether precipitation occurs.
A 1033 MB Canadian high which tracks from the Northern Plains into the Upper Midwest will dominate the weather Friday and Saturday, and will drive cold air advection over the region, helped by a broad planetary trough stretching from Manitoba to the Labrador Sea. Aided by radiational cooling, lows will be below freezing both Friday night and Saturday night, leading to our first two autumn frosts. High Pressure will move out of the region Sunday and a low pressure system will track towards the Midwest from the Plains, leading southerly warm air advection and increasingly stronger winds through the day.

Robert Kelnosky

Monday, October 12, 2015

Cooler Week Ahead

Public weather briefing

After a warm weekend, temperatures seem to be dropping to the 60s.  It will be cloudy and slightly breezy until Tuesday night. There will be clear skies on Wednesday until the clouds return on Thursday. There is a chance of rain Thursday afternoon and evening, but other than that, it seems like we will not see any rain in the near future.

Forecast 

Tonight. Cloudy and breezy. Low around 46.

Tuesday. Partly Cloudy. High around 60.

Tuesday night. Clear skies and light breeze. Low around 40.

Wednesday. Clear skies and sunny. High in the mid-60's, low in the lower 40's.

Thursday. Cloudy with showers likely in the afternoon and evening. High in the lower 60's, low in the lower 40's.

Outlook for Friday through Sunday. It will be partly cloudy on Friday with the skies clearing up mid-day Saturday. After that, the weekend should be sunny. Highs will be in the lower 50s and lows will be in the lower 30s for Friday and Saturday. On Sunday, the low will be in the 40s.  [CONFIDENCE: MEDIUM]

Forecast Discussion

A low pressure system located to the North of Wisconsin in Ontario caused a cold front to recently move through Wisconsin causing the recent drop in temperatures. Strong winds follow the cold front. Cold air advection will continue from the North which will cause temperatures to be in the lower 60s in the near future. Skies should clear behind the cold front until another low pressure system moves southeast bringing Madison some rain and light breeze. There is a broad ridge over the most of the western United States causing clear skies and warmer temperatures. 

Alex Delvoye

Thursday, October 8, 2015

A Cooler Week Coming? Not so fast.

Public weather briefing

After a warmer than average week, temps will be dropping slightly this evening as cooler air moves into the region from the north.  This evening a slight chance of light rain exists but it is unlikely throughout the night.  The next couple days will be pleasant with mild temperatures and mostly clear skies.  As next week begins, warmer temperatures are expected to return.  There is a slight chance of showers on Monday but nice weather similar to this week will follow.  
  
Forecast 

Tonight. Slight chance of showers early in the evening.  Lows in lower 50's. 

Friday. Overcast in the morning with gradual breakage in cloud cover later.  High of 58.  

Friday night. Mostly clear skies with lows in the lower 40's.

Saturday. Sunny and warmer with a high of 68.

Sunday. Sunny and warmer with a high of 75.  

Outlook for Monday through Tuesday. Slight chance of rain on Monday with a high of 68.  Tuesday will be slightly cooler but clear with a high of 63.  Lows will be in the mid-40's.[CONFIDENCE: MEDIUM]

Forecast Discussion

A low pressure center situated over northern Wisconsin has moved in from Manitoba forcing cold air advection into the midwest. Accent and moderate rain is being driven east of the low by differential warm air advection from the southwest while some showers may be expected in southern Wisconsin along the cold front.  With the passage of the front, temperatures will quickly drop into the mid-50's with dew points in the upper-40's.   As the cyclone tracks eastward, cooler temps will remain into Saturday morning but with a warming trend beginning in the afternoon as the short wave trough passes and zonal wind advects warm air from the plains.  


Alexander F. Fox

Wednesday, October 7, 2015

A warm Sun(ny)day ahead

Public weather briefing


Settled and mild weather has been present for a reasonably long period now, with high temperatures in the high 60's and low 70's, as well as mostly sunny skies. This looks likely to end on Thursday as showers and thunderstorms are of high possibility. Over the next few days there will be a good variation in temperatures - Friday will see temperatures below the average for this time of year, whilst on Sunday temperatures will reach the high 70's, much higher than normal for this time of year.

Forecast 

Tonight. Partly cloudy with light easterly winds, becoming more southerly into early Thursday morning. Low around 50F.

Thursday. High possibility of showers and thunderstorms in the late morning and early afternoon. Cloudy throughout the day with a moderate southwesterly wind and strong gusts. High around 74F.

Thursday night. Cloudy and mild, with a small chance of showers in the early evening. Low in the lower 50's.

Friday. Mostly cloudy but brightening up as the day progresses. Light northwest wind. Cooler temperatures, with a high of 59F. Over night will be relatively clear, making for a cold night, with temperatures dropping to around 42F.

Saturday. Mostly sunny conditions. High near 64F, low over night around 51F.

Outlook for Sunday through Tuesday. Sunny and much warmer temperatures for Sunday, reaching around 77F. Monday will be windy, still warm temperatures for this time of year, with a high in the high 60's. Mostly clear on Tuesday. High in the mid 60's. Lows will be in the high 60's over Sunday night and in the mid 40's over Monday and Tuesday night. [CONFIDENCE: MEDIUM]

Forecast Discussion

 Surface high gradually moving east of Madison gives rise to winds becoming light and southerly over Wednesday night. A surface low moving eastward behind it will reach MN by Thursday morning, bringing precipitation ahead of it as warm air advection occurs, with rain expected over Madison by Thursday midday.
 On Thursday evening southern Wisconsin is in the right entrance region of the upper level jet, causing weak upper divergence and upward motion, giving rise to the possibility of precipitation. As the low pressure system moves eastward, away from the area, cold air advection will drag cold air from Canada over Madison. This results in much cooler temperatures on Friday.
 By Friday afternoon the upper level trough axis is to the southeast of Wisconsin, resulting in upper convergence and downward motion. This will bring clearer skies and settled conditions.
 By Friday evening the center of the surface high is across Madison and upper level divergence is neutral. This allows for clear skies overnight, causing strong radiative cooling over night.
 Strong warm air advection is present on Saturday and the upper level jet becomes zonal over southern Canada. A southern flow, along with continued warm air advection for Sunday gives higher than average temperatures for this time of year.
 An upper level shortwave trough is present over northern Wisconsin and strengthens in the early part of next week. Conditions will be settled.


Rich Johnson

Tuesday, October 6, 2015

Rain, rain don't go away

Public weather briefing

Persistent mild temperatures for early October weather. High temperatures have been the upper 60's to lower 70's with light winds. There is an anticyclone that has been present over the Midwest providing sunny skies throughout the week. This has provided good fall like weather for much of the week, but it looks like sunny skies will not last in the next couple days. 

Forecast 

Tonight. Clear skies with a light wind. Low in the lower 50's.

Wednesday. Sunny with light winds. High around 70.

Wednesday night. Clear with continued light wind.  Low in the lower 50's.

Thursday. Chance of thunderstorms in the afternoon. High around mid-70's

Thursday night. Slight chance of some rain. Low in the lower 50's.

Outlook for Friday through Sunday. Overcast on Friday, and clearing up Saturday and Sunday.  Highs in the high 50's Friday, mid-60's on Saturday and low 70's on Sunday. Lows in the 40's on Friday, and in the 50's on Saturday and Sunday. [CONFIDENCE: MEDIUM]

Forecast Discussion

The high pressure system that has been stationed over Madison will provide a nice day on Wednesday with temperatures in the mid 70's with light winds and abundant sunshine. A low pressure system from Western Canada will move into the area on Thursday bringing a chance for some rain and a bit warmer temperatures as well as higher humidity. This low pressure system will be pushed eastward by a high pressure system that originated in Montana on Thursday night into Friday. As the low pressure system moves eastward it drags down cold Canadian air (seen on 850mb map) causing the the high temperature to be in the 50's on Friday with variable winds. Then by the weekend this high pressure system spanning most of the great plans and upper midwest brings warmer temperatures again in the mid-60's on Saturday and mid-70's on Sunday with clear skies. 

Anna Sienko

Monday, October 5, 2015

Fall weather is here to stay!

Public weather briefing

The cool, fall air is here to stay. Temperatures are to stay in the 60's during the daytime hours with low 50's at night. Thursday brings a chance of rain, which will bring slightly cooler temperatures and light winds. Other than Thursday, the rest of the week will greet us with clear skies and nice fall temperatures, making it an enjoyable week for walking on campus.

Forecast 

Tonight. Partly cloudy. Lows in the lower 50's.

Tuesday. Clear skies. Highs in the upper 60's.

Tuesday night. Clear skies with light winds.Lows in the lower 50's.

Wednesday. Clear skies with light winds. Highs reaching the lows 70's.

Thursday. Chance of rain. Highs reaching the high 60's.

Outlook for Friday through Sunday. Clear skies throughout the weekend. On Friday, highs in low 60's, and lows in the 40's. For Saturday and Sunday, highs reaching the upper 60's, with lows in the upper 40's. [CONFIDENCE: MEDIUM-HIGH]

Forecast Discussion

A high pressure system stays directly over the Midwest, allowing for clouds to clear as the week moves forward. Consistent temperatures will be observed as well, being mid-60's during the day, which 50's at night. We will be affected by a slightly increased temperature gradient associated with a cyclonic system over the Hudson Bay, bringing slight winds to the area around Tuesday night. A small low, originating from western Canada, will reach the Midwest around Thursday, bring a small amount of precipitation with an it's associated warm front. Just behind the precipitation will be a time of warmer temperatures brought in from the same cyclonic entity. Not predicted to be very organized, the low will soon pass, with another high pressure system following by the weekend.

Tyler Wright

Friday, October 2, 2015

Clear skies for the weekend!

Public weather briefing

After what some may call an abrupt cool-down, we can expect these fall-like temperatures to stick around! Temperatures are expected to hover between the between the 40s and 60s over the next week. In addition to these temperatures, it's expected to be a bit breezy this weekend, so bundle up if making a trip to the apple orchard or to the Badger game! Clear and partly cloudy skies are expected over the weekend and into next week. However, looking into late next week, there is a possibility of some rain.

Forecast 

This afternoon. Sunny. High in the lower 60's.

Tonight. Clear and cool. Low in the lower 40s.

Saturday. Sunny and breezy. High in the lower 60s.

Saturday night. Clear and cool. Low in the mid-40's.

Sunday. Partly cloudy. High in the upper 50s.

Monday. Partly cloudy. High in the low 60s.

Outlook for Tuesday through Thursday. Clear Tuesday, rain is possible on Wednesday, with higher chances of rain expected Thursday. Highs in the mid to upper 60s Tuesday, Wednesday and Thursday. Lows in the 50's. [CONFIDENCE: MEDIUM]

Forecast Discussion

We are currently situated on the southern side of a high pressure system centered in Canada, which will bring easterly winds to Wisconsin. These easterly winds will keep our temperatures and weather consistent over the weekend (highs in the 50s). A new high pressure system will be in our vicinity early next week as the former system progresses further north into Canada. This will give way to more clear skies. This new system will be centered over Indiana and Ohio and will provide some southerly winds and some slightly warmer temperatures than what is expected this weekend (highs in the 60s). As this second high pressure system phases out of the Midwest, there is a potential for rainfall late next week as a low pressure system could make its way toward Wisconsin from the southwest.

Lauren Deanes