Area Forecast Discussion
Issued by NWS Twin Cities, MN
Issued by NWS Twin Cities, MN
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114 FXUS63 KMPX 091949 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 249 PM CDT Thu May 9 2024 .KEY MESSAGES... - Frost/Freeze likely across portions of northwest Wisconsin tonight. - Scattered thunderstorms, some potentially severe, Friday afternoon across eastern Minnesota & western Wisconsin. - Above-normal temperatures this weekend into next week. && .DISCUSSION... Issued at 249 PM CDT Thu May 9 2024 Isolated showers and blanketing stratus across western WI and southern MN continue to retreat to the south as surface low pressure progs east over the upper-Ohio River Valley region. Aside from remnant scattered cu developing from peak daytime heating, temperatures are expected to reach the mid to upper 60s. Tonight`s forecasted lows will widely range from the upper 40s in western MN to near freezing in portions of interior west-central WI. Northeasterly flow combined with clearer skies will allow for some areas in WI to see potential frost Friday morning. So if you have any vegetation that is sensitive to temperature, you may want to consider taking protective measures. The main course for today`s discussion focuses on the forecast for Friday. An upper-level shortwave over Saskatchewan and Manitoba descends south over the northern plains beginning Friday morning. NW winds will increase between 30-35 mph across western MN as it lays on the periphery of the pressure gradient. Best forcing for precip development looks to reach central MN and Western WI by Friday afternoon. Consistent with the previous discussion, timing of forcing arrival aligns with peak diurnal heating, thus an increased potential of organized convection. The Storm Prediction Center has issued a marginal risk (level 1 of 5) for severe convection Friday afternoon and evening. Forecast soundings present an environment of only a few hundred joules/kg of elevated MUCAPE and inverted-V soundings. Therefore hazards look to mainly be limited to isolated strong gusty winds and potentially some hail in the strongest storms. QPF as of now looks to range between a few hundredths to a quarter of an inch with Western WI have higher confidence of observing near the quarter inch mark. Storms will quickly clear out Friday overnight with lows in the 40s. This weekend looks overall relatively quiet as the northern plains falls under split flow. Winds will remain slightly increased with gusts up to 25 mph along with RH values nearing 30 percent, elevated fire weather conditions will exist. Saturday will be a great day to get outside and enjoy temperatures in the upper-60s to mid-70s with only scatted afternoon cu to disrupt plentiful sunshine. Sunday, the maxima of the h85 thermal ridge will advect east and allow highs to reach the low 80s for much of the area. A weak shortwave develops over the Dakotas Sunday afternoon which could potential generate a few showers however there is disagreement amongst long-term ensemble membership, thus maintained NBM PoPs of 30 percent mainly east of the I-35 corridor. Looking into early next week, multiple shortwaves bring periods of precipitation although QPF advertising only light rainfall accumulations. An upper-level wave sweeps across the Northern CONUS by the middle of next week which could be bit more robust but will need to continue monitoring. Temperatures will range near climatology for this time of year which is in the upper 60s. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1207 PM CDT Thu May 9 2024 VFR conditions expected throughout this TAF duration with MVFR- worthy stratus earlier this morning continuing to dissipate, resulting in mid-level fair wx cumulus clouds through the rest of the daytime hours. High clouds will begin streaming in from the west overnight, eventually becoming mid-level ceilings late Friday morning into Friday afternoon. Chances for precip increase over far eastern MN into western WI around the 18z hour so have included precip at the tail end of the MSP and WI TAFs to account for that, with more details coming in later TAFs. Breezy NE winds through this afternoon will diminish later this evening and overnight, then picking up from the SW during the day tomorrow. KMSP...Main complication will be the incoming rain early Friday afternoon, potentially slightly earlier than 18z. Any rainfall is expected to be light but CB/TS/MVFR conditions cannot be ruled out, however chances for such conditions are too low for inclusion at this point. /OUTLOOK FOR KMSP/ SAT...VFR. Wind NW 10G20 kts. SUN...VFR. Wind W 15G25 kts. MON...VFR. Wind variable 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...Frost Advisory from 2 AM to 8 AM CDT Friday for Barron- Chippewa-Eau Claire. Freeze Warning from 2 AM to 8 AM CDT Friday for Rusk. && $$ DISCUSSION...Dunleavy AVIATION...JPC