000 FXUS63 KMPX 021948 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 248 PM CDT Fri Jun 2 2023 .DISCUSSION...(This evening through Friday) Issued at 248 PM CDT Fri Jun 2 2023 KEY MESSAGES: - Much above normal temperatures continue through Monday with highs in the mid 80s to lower 90s, which are near record highs. - Scattered afternoon and evening thunderstorms today and again on Saturday. - A frontal passage Monday will start to cool us down and provide another chance for thunderstorms. Today through Monday... High temperatures and high precipitable water will lead to an environment primed for heavy rain. This morning's sounding at MPX had a precipitable water value of 1.49 which is near the maximum based on sounding climatology. Despite this there is no good forcing mechanism present and little shear to get much organized convection. So we expect to see continued airmass thunderstorms this afternoon and evening. Slow storm motions and high precipitable water will lead to the main threat being for heavy rainfall. The lack of shear and forcing means strong to severe storms are not likely. Scattered cloud cover has lead to some areas under-performing on temperatures as mentioned in the previous discussion. Saturday will be similar to Friday, but a little drier as the upper high moves over the Upper Midwest from the Great Lakes. So expect another hot day with highs near 90 and afternoon/evening thunderstorms. The increasing dryness trend will continue into Sunday with lower chances, but still possible, afternoon and evening thunderstorms. This could also then be a much sunnier day and with the same airmass present we could therefore see our highest temperatures of the week. Monday will be the start of a change as a cold front moves through the Upper Midwest and a surface high pressure moves in behind it. The timing of the frontal passage will greatly impact the weather we will get. If it passes in the afternoon or evening we will still see a hot day with a good chance for some thunderstorms from all the instability built up during the day. If it passes through in the morning though it will be cooler, more stable and less likely to see any storms. The front could be through northern portions of Minnesota by Monday morning, but how much of Minnesota further south and Wisconsin sees the instability build is still uncertain. Best chance for another hot day and thunderstorms will be in southern Minnesota. Tuesday through Friday... Behind Monday's front high pressure will be over the region. This will be a much drier air mass with dew points only in the 40s. So even through we will be cooler we could still see relative humidity in the low 30s to even 20s. This could provide for a fire weather risk. Under the surface high precipitation chances will be much lower, but there is some variability between deterministic models in how much this high dominates. If it is a little farther east or weaker we could still see some storms later in the day across parts of western Minnesota during this period. Tuesday will likely be the coolest day, with a gradual warming trend through the end of the week. The only near normal temperature day may be Tuesday with a chance of it on Wednesday with above normal favored again for Thursday and Friday. If we do not see much rain this could favor drought development. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1203 PM CDT Fri Jun 2 2023 It will be another tricky day of where showers and thunderstorms will occur. Currently, a few pop-up thunderstorms are located over southeastern MN. These are expected to be short-lived but their northward movement and eventual generation of an outflow boundary should kick off additional convection as we progress through this afternoon. Have opted to include TEMPOs for -TSRA late this afternoon for our more eastern terminals (MKT, MSP, RNH, EAU) where better instability and a more organized upper-level circulation exist. Visibilities could reduce to MVFR within any storms. Otherwise, the rest of the period will have VFR conditions and winds ranging from the southeasterly to more easterly. Speeds will be near 10 knots this afternoon, slightly slowing to near 5 knots this evening. KMSP...Have added vicinity thunderstorms mention in the prevailing as convection has begun to develop south and southeast of the metro. Best chances for thunderstorms will be from 21z to 01z as the outflow boundary from the stronger convection near Northfield pushes north. MVFR visibilities are possible within any storms. /OUTLOOK FOR KMSP/ Sun...VFR. Wind ESE 5-10kts. Mon...VFR. Chc aftn/eve MVFR/TSRA. Wind NE 5-10kts. Tue...VFR. Wind E 10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...NDC AVIATION...CTG