Wednesday, September 30, 2015
We had quite the warm weekend, but things are cooling down drastically. We experienced some cooler weather on Tuesday, but the temperature is suppose to get down into the low 60's, and even high 50's (degrees Fahrenheit)! We experienced a strange rainstorm which brought 2 inches of precipitation with it, but the rest of the week is looking dry. It looks like Fall is right around the corner!
Wednesday Night. Clear. Low near the lower 40's (wow!)
Thursday Night. Still Clear. Temperature getting down into the lower 40's.
The presence of a trough north of Wisconsin is the reason why Wisconsin is getting a lot cooler throughout this week. The winds flowing upstream between the ridge and the trough are bring the cooler airs from the northern parts of Canada southward. This trough will move eastward throughout time, and downstream of the trough, the height contours become very meridional and the upper level winds become very strong. Following the trough is a weak surface anticyclone that was present in North Dakota/Minnesota. However, as time will progress and as the trough moves eastward, the anticyclone will follow the trough and strengthen dramatically, reaching a pressure of around 1046mb!
It's important to note that Tropical Storm Joaquin is present off the southeast coast of Florida, but it's difficult to predict where it will hit land. Lastly, there's a huge trough over the south coast of Alaska that a strong surface cyclone is associated with. However, due to curvature and the physical features along the coast of British Columbia, it will become somewhat stationary along the coast. (but not weaken!)
Nicholas J. Vertz
Public weather briefing
Fall is finally here! Just a few days ago Madison was seeing lots of warm moist air coming up from the Gulf of Mexico which was keeping our late September in the mid to upper 70s with high humidity. However, since then, a strong high pressure system has moved into the area causing cooler but dry temperatures in the Midwest. Great fall hiking weather is expected all week with highs of 60 and lows of 40. The first weekend in October will be free of precipitation and mostly sunny, perfect for autumn activities.
Tonight. We are looking at a beautiful fall day with highs near 60, plenty of sunshine and moderate winds. Tonight the low is expected to drop down to a chilly 40 degrees, however, no rain is expected.
Thursday. Thursday, similar to Wednesday, should be another great first day of fall with a high of 61 and low of 41. Moderate winds are expected.
Thursday night. Clear and cool. Low in the low 40's.
Friday. Should be mostly sunny all day with moderate winds and a high of 61.
Outlook for Saturday through Sunday. Once again, great fall weather is expected with highs around 61 and overnight lows in the lower 40s. [CONFIDENCE: HIGH]
High temperatures will remain in the uppers 50s and low 60s due to a high pressure system (1030 mb) currently located in northern Wisconsin. The system is not likely to move out of the area anytime this week because it is situated between a strong low pressure system to the east and a high pressure wind to the north in Ontario/Quebec. The combination of these two features and the fact that the great lakes region is located below the left jet entry region will produce lots of upper level convergence and in so, downward vertical motion. Low temperatures at night are expected to drop to the low 40’s but not low enough for frost to form. Dry air from the north will cause the lowest dew points in the afternoon by boundary layer mixing. Surface winds are expected to increase over the weekend due to the strong pressure gradient across southern Wisconsin, which is expected to intensify.
Monday, September 28, 2015
Public weather briefingWe're on the theoretical last leg of warm weather! (Yay for fall?!) After the consistently warm temperatures we've been having, this week might be a slight shock to the system. There will be rain much of this evening, starting after the Packer game tonight (around 11PM) and taping off in the morning, by about 10AM. Clouds will clear throughout the day Tuesday and the temperature will reach a mild mid-60s. The rest of the week will bring consistently sunny skies and temperatures in the low-60s.
Tonight. Rain for much of the night, starting after ten and ending around mid-morning Tuesday. Up to a half inch of rain is expected. Temperatures will drop throughout the night, with lows in the upper 50's.
Tuesday. Rain tapering off by 10, clouds clearing into a sunny afternoon. High of 64.
Tuesday night. Clear and cool. Low in the lower 40's.
Wednesday. Sunny but remaining cooler. High just above 60. Low around 42.
Thursday. Continued sunny with light winds. High around 62.
Outlook for Friday through Sunday. It will remain mostly sunny and clear for the rest of the week. Temperatures will climb to about 60 each day, and fall to about 40 at night. [CONFIDENCE: MEDIUM]
A line of precipitation will sweep through the area tonight. The band is associated with a low pressure system located all the way over the Hudson bay, and stretches across much of the Great Plains. Location from Madison to western Nebraska will receive rain accompanying this system. Geopotential gradients over the continental United States are weak, however the two impressive low pressure systems located in far northern Canada are forcing the upper level flow regimes. There will be a strong jet streak that builds from northern Minnesota to the tip of Quebec. As the system moves downstream, it will become almost linear, and Wisconsin will be on the northern jet entry region. This will result in convergence aloft and sinking air, bringing us sunny days. Additionally, the downstream propagation of the system will usher colder air from Canada into our area, resulting in our cooled temperatures.
Thursday, September 24, 2015
Public weather briefingThis warm air must love Madison as much as I do - it does not seem to want to leave! These warm temperatures and low dew points are sticking around for the weekend, making it the perfect weekend to enjoy the outdoors before it really starts to feel like fall. With high temperatures staying in the mid-70s and low temperatures staying in the 50s throughout the weekend, it is the perfect time to get in that last cookout or lake swim. As for changes in this beautiful weather we are experiencing, expect tomorrow to be a little bit cloudy, but with the same great temperatures we have had this week, and expect temperatures to increase a little bit toward Sunday afternoon and Monday of next week. Enjoy this last bit of summer while you can!
Tonight: Lows in the 50s, with potential cloud cover coming from storms to our west.
Friday: Highs in the mid-70s, with partly cloudy conditions.
Saturday: High temperature around 75, with lows in the mid-50s.
Sunday: Warmer temperatures coming, with highs in the upper 70s and lows in the upper 50s.
Outlook for Monday-Wednesday:
The week starts off warm, with warm air coming in from our
south, but this warm air looks like it will pass and be replaced with cooler
air from our north around mid-week. Check back on Monday of next week for a
more updated forecast! [CONFIDENCE: MEDIUM]
There is a beautiful upper level ridge building over the central US right now, keeping Madison warm and dry for the weekend. The dissipating low-pressure system to our west is bringing us some cloud cover for tomorrow, and the low-pressure system moving up the eastern coast has the potential to bring clouds to the area later in the weekend, as moisture from this system gets caught in the anti-cyclonic flow over the central US and moves westward towards Madison. As the weekend progresses, winds gradually shift from more easterly and southeasterly to southerly winds, bringing us the warmer temperatures at the end of the weekend. This ridge currently over the central US is predicted to move downstream and clear the area by early next week, at which time we may be subject to protruding Canadian air from the north and therefore cooler temperatures. While we weather geeks may be upset that there is not much weather going on right now - to you I say, "Build a ridge and get over it!"
Wednesday, September 23, 2015
Public weather briefingToday is the Autumnal Equinox, but it sure felt quite a bit like summer. The beautiful weather we have had this week is likely to continue over the next couple of days, and we should remain rain-free as we head into the weekend. Storms over the Great Plains could send clouds our way on Thursday, but these should clear up by Friday morning. Low temperatures tonight may fall a bit below normal, and there is a good chance that it will become very humid overnight. However, daytime highs in the next few days are likely to reach the mid 70's, exceeding the average temperature by a sizable amount and reducing the relatively humidity to a comfortable level. Although Autumn is technically here, you can plan on keeping the fall sweaters packed away at least until next week.
Tonight. Clouds rolling in from the West. Lows in the low 50's.
Thursday. Partly cloudy AM, breaking up later in the day. High around 76.
Thursday night. Warm and humid. Low in the upper 50's.
Friday. AM clouds and PM sun. High near 75. Low in the mid to low 50's.
Saturday. Mostly sunny. High near 76. Badger football kickoff temperature around 68.
Outlook for Sunday through Tuesday. Warm temperatures remain through Monday, with highs in upper 70's. Winds to pick up late Sunday, coming from the southwest. Cooler and partly cloudy on Tuesday, with a chance of rain and a low in the mid 50's. [CONFIDENCE: MEDIUM]
A surface low pressure system over Nebraska and South Dakota is expected to weaken as it moves toward a relatively stronger high pressure center over western Ontario. This should keep any precipitation well north of Madison on Thursday. In addition, an 850mb high centered over the eastern Great Lakes looks to remain stationary over the next two days, providing Wisconsin with the sustained warm temperatures we are likely to experience at the surface.
Convergence of 850mb geostrophic wind over northern Wisconsin on Monday could force a tighter temperature gradient and produce a thermally direct circulation over the northern half of the state and into Ontario. The cold air forced downward is likely to result in a (somewhat weak) cold front at the surface, leading to slightly cooler temperatures in Madison on Tuesday.
Tuesday, September 22, 2015
Public weather briefingThis week will be full of warm temperatures and partly cloudy days. Wednesday through Monday will be have highs in the upper 70's and lows in the upper 50's. There will be relatively low wind speeds making the warm temperatures feel a touch warmer. Fall colors will be a little later this year due to the warm temperatures that have been occurring in September thus far.
Tonight. Calm with partly cloudy skies. Low of 57.
Wednesday. Partly cloudy with light winds. High of 78.
Wednesday night. Partly cloudy with low wind. Lows in the upper 50's.
Thursday. Partly cloudy with light winds. High 76. Low around 54.
Friday. Partly cloudy. High near 77.
Outlook for Saturday through Monday. Clear skies Saturday and Sunday, with a small chance of rain Monday. Highs in the mid 70's Saturday and Sunday and Monday, Lows in the mid to 50's. [CONFIDENCE: HIGH]
There is a strong cyclone centered over the Hudson Bay region that would have the potential to produce weather for us if it would have moved south. The cold front associated with this cyclone will stay to our north. We will have some slight warm air advection, but with wind speeds across the midwest being quite low, there won't be too much of an effect. We are under a broad ridge in the upper troposphere which will keep our skies storm free for the next couple of days. Warm temperatures will persist for the next couple days as well.