Area Forecast Discussion
Issued by NWS Twin Cities, MN
Issued by NWS Twin Cities, MN
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104 FXUS63 KMPX 051150 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 650 AM CDT Fri Jul 5 2024 .KEY MESSAGES... - Scattered showers continue this morning, with a morning break before further scattered showers and weak storms return this afternoon and evening. - Diurnal showers and weak storms possible this weekend and into the beginning of next week. && .DISCUSSION... Issued at 308 AM CDT Fri Jul 5 2024 Our low pressure center is located in far eastern Minnesota and western Wisconsin this morning evidenced by the slow moving rotating showers that have persisted over the past few hours. These slowly rotating showers will continue to churn near the surface low through sunrise as the low begins to push eastwards. The showers tonight have largely remained just north of our coverage area towards central Minnesota and northern Wisconsin, covered by our neighboring WFO Duluth, with the two main showers over our area affecting portions of McLeod, Sibley, Dakota, and Scott counties. Isolated to scattered showers are likely to continue throughout the day until the system is fully out of the area, which looks to happen by later this evening to early Saturday morning. Due to how scattered showers are expected to be today versus yesterday, additional accumulations resulting in 2 day totals above an inch will be locally isolated, favoring the areas that have been seeing the rainfall overnight. Outside of the showers this morning has been persistent fog as a result of the weak winds under the surface low alongside lingering moisture, with visibility dropping below 1/4 mile in spots favoring western Wisconsin. Fog should also begin to dissipate as the surface low tracks eastwards and winds strengthen just enough to mix us out. High temperatures this afternoon in the mid 70s alongside lower overall shower coverage should make for a nice day in many spots, as long as you can avoid or tolerate the passing showers. As the near-term system winds down, we do not truly see another widespread synoptic scale event within the scope of the 7 day forecast, with a diurnally driven pattern favoring isolated to scattered showers and weak thunderstorms through the weekend and into next week. Flow aloft stagnates as a trough spanning almost the entire CONUS swings its apex south of the area, with weak upper level flow as a result with a lack of significant shortwave energy to help force stronger storms. Unlike the past few weeks, we also do not see a strong low level jet influencing our pattern, with lower overall moisture content to work with. Our main forcing will likely be diurnal heating with a hint of shortwave perturbations, enough to cause some nuisance showers and storms but not enough to produce any significant wet signal or thunderstorms. Instability generally looks meager with forecast soundings from the GFS peaking at around 1000- 1500 J/KG largely surface based with adiabatic lapse rates near the surface becoming much less favorable aloft. Based on current guidance, the best day to have a chance at more widespread showers looks to be Monday as the upper level trough begins to occlude and produces forcing that is a bit better compared to the weekend. After Monday, our flow aloft turns northerly as a ridge builds over the Rockies, setting up what looks to be a trend towards warmer weather as we get into the middle of the month. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 650 AM CDT Fri Jul 5 2024 Scattered showers continue across eastern MN and northwest WI. These could linger into the afternoon across western WI, so introduced a prob30 at EAU later this morning. IFR cigs are expanding across eastern MN, but some improvement is expected to occur between 15-16Z while MVFR cigs prevail for a few hours after that. More scattered showers and a few isolated storms are expected this afternoon across western MN. KMSP...IFR conditions now, but cigs should begin rising after 15Z. A couple showers just south of the terminal should continue sinking south with dry conditions likely the rest of the day. /OUTLOOK FOR KMSP/ SAT...Chance PM MVFR/SHRA/TSRA. Wind SW 5-10 kts. SUN...VFR. Chc aftn SHRA/TSRA. Wind SW 10-20 kts. MON...VFR. Chc aftn SHRA/TSRA. Wind WNW 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...TDH AVIATION...Borghoff