Area Forecast Discussion
Issued by NWS Twin Cities, MN
Issued by NWS Twin Cities, MN
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335 FXUS63 KMPX 262355 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 655 PM CDT Wed Jun 26 2024 .KEY MESSAGES... - Quiet weather continues the rest of today and most of Thursday, with our next round of showers and thunderstorms arriving late Thursday through Friday morning. - Quiet weather again this weekend, followed by what looks to be our strongest weather system of the period arriving Monday into Tuesday. && .DISCUSSION... Issued at 244 PM CDT Wed Jun 26 2024 If you have not had the chance to get outside and enjoy the fabulous weather today, we highly recommend doing so! Temperatures in the mid to upper 70s continue under isolated to scattered cumulus with satellite imagery showing a lack of significant cloud cover over the entirety of the MPX CWA. There are denser blankets of cloud cover over portions of northwestern Minnesota that are slowly drifting southwards, however by the time they arrive we will be losing our daylight and with that the efficient mixing required to keep them, with our cloud cover remaining sporadic overnight as temperatures fall into the 50s. Tomorrow will be similar to today except with increasing cloud cover as an upper level jet slides across the area ahead of a strengthening 850mb jet that will develop later in the day towards Friday morning, introducing our next chance for more widespread showers and storms through Friday morning. As the jet strengthens and moves towards Minnesota from the west, expect increasing cloud cover and chances for showers beginning Thursday evening but becoming more likely after midnight. There is a chance for thunderstorms within the showers with strong forcing supplied by the LLJ, however instability is fairly limited due to cooler temperatures and lapse rates are poor such that severe weather is not currently expected. Most guidance produces a weak surface low over northern Minnesota towards the nose of the jet Friday morning, with a weak cold front sliding southwards across the area with showers becoming isolated into Friday afternoon before dissipating completely. As the showers wrap on Friday, the weekend looks to return to quieter conditions as we transition towards the next bigger system arriving early next week. Zonal flow aloft Saturday into Sunday coincides with the occlusion of the surface low from Friday, which by Saturday is over the Great Lakes and by Sunday is pushing over the Atlantic. Weak surface high pressure slides across the area with weak subsidence as upper level flow turns northwesterly on the western side of the departing trough. Temperatures generally remain comfortable in the mid 70s for highs and 50s for lows through Tuesday. Our next larger system looms by the second half of Monday with a digging upper level trough over western North America producing a surface low with yet another strong 850mb jet advecting moisture northwards from the southern CONUS. Ensemble guidance shows a varied range of precipitation amounts such that confidence in area totals is low at this point, with significant differences both run to run and between different deterministic solutions. A prime example being the FV3 core struggles to produce a surface low but keeps widespread showers as a result of the LLJ strength, meanwhile the ECMWF/CAN models prefer a moderately strong surface low moving through southern Ontario from west to east, dragging a cold front across the region by Tuesday morning. The latter solution would result in more significant precipitation potential as well as a better chance for thunderstorms with a much better shear and instability profile ahead of the cold front late Monday into Tuesday. For now, expect another wet 24-36 hour period beginning Monday afternoon through Tuesday with the potential for more significant precipitation accumulations than the incoming Thursday/Friday system. We will continue to monitor the trends and provide updates as we hopefully get better alignment of guidance over the weekend. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 622 PM CDT Wed Jun 26 2024 VFR conditions expected through the period. Mostly scattered to clear skies across the region this evening as portions of the afternoon cu field will likely stick around through late tomorrow morning. The low VFR clouds will start to fill back in tomorrow afternoon, with mid and high clouds increasing from west to east ahead of an incoming weather system. Northerly winds may be a little gusty to start the period, but will become light overnight and gradually shift out of the SE by tomorrow afternoon. KMSP...Opted to keep a layer of clouds around 6k ft through tomorrow evening given the latest trends, but there is still a period tomorrow morning that could clear out for a few hours depending on how the cu field persists overnight. Rain could start as early as 03z tomorrow, but should be just VFR -SHRA so have kept mention out for now. No additional concerns. /OUTLOOK FOR KMSP/ FRI...VFR/MVFR, chc -TSRA. Wind SE 10-15 kts. SAT...VFR. Wind NW 10-15G25 kts. SUN...VFR. Wind N bcmg SE 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...TDH AVIATION...BED