919 FXUS63 KMPX 191146 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 546 AM CST Tue Nov 19 2019 .SHORT TERM...(Today through Wednesday) Issued at 321 AM CST Tue Nov 19 2019 Frontal boundary continues working slowly east this morning, with the advertised band of precipitation out ahead of it in conjunction with PV advection aloft. As of early this morning, the band has transitioned mostly to snow given cooling low level temperatures overnight. However, the band has been and will continue to weaken over the next few hours. Some light snow accumulations are possible which could lead to a few slick roads east of the I-35 corridor and generally north of the metro. Winds have already turned northwesterly across western MN, a trend that will follow the front eastward through the area, with the front pushing east of Eau Claire by this afternoon. Surface high pressure will build in from the west keeping winds light. However, boundary layer moisture will remain very high despite this, and model condensation pressure deficits have a good handle on low stratus currently in place east of a Alexandria to Mankato line. CPDs indicate the stratus should basically hold in place across the area, with an expansion of clouds across western MN later today where it was clear overnight. Increasing southeasterly winds and warm air advection aloft will precede the approaching system for Wednesday. Temperatures in the low to mid 40s are likely. Forcing for ascent will remain north of our area as the upper jet streak and PV advection tracks east across North Dakota to northern Minnesota. .LONG TERM...(Wednesday night through Monday) Issued at 321 AM CST Tue Nov 19 2019 Main concern during the long term is with the system that will impact the region Wednesday night into Thursday. Otherwise, the weather through Tuesday of next week looks to be quite with seasonable temperatures. For our system Wednesday night, model agreement has become pretty strong on the large scale, with a surface low following a roughly Omaha to Green Bay path as the remnants from the h5 low still west of the Baja Peninsula this morning ends up in the western Great Lakes by Thursday morning. As for what's changed since the last forecast cycle, well, very little. Very warm air at the onset Wednesday evening will result in all rain across the entire MPX CWA as precip breaks out, but we will see rain change to snow from the northwest to southeast during the night into Thursday morning. However, p-type looks to remain all rain for Mankato, the Twin Cities, and west central WI though Wednesday night, with the transition to snow in these areas not happening until Thursday morning. Greatest threat for more significant snow accumulations will be up across northern MN, but we could see snow totals pushing 2 inches along and west of a Granite Falls to Little Falls line depending on how quick the transition happens. As for that transition, we favored a slower (ie. warmer) GFS/ECMWF solution, with NAM boundary layer temps through the course of this event way to low, which results in it changing over to snow too soon. The one interesting aspect with this system is the anomalously high moisture associated with it. Pwats into the warm sector will be up around 1.2" up into southeast MN, which is 300% of normal. In addition, integrated water vapor transport standardized anomalies from both the ECMWF and GFS are progged to be up around 5 standard deviations above normal, which is a return period of 1 day every 10 years. So this will pack a bit of a punch for rainfall. It does appear we'll have a band of enhanced QPF along where surface convergence is maximized along the warm front, where rainfall totals over an inch are very plausible. Right now, Rochester to Eau Claire areas look to have the greatest potential getting enhanced rainfall like that. For MSP, we're now just 0.87" of liquid short of 2016 for wettest calendar year on record and it's looking likely that we'll get over half of that with this system. Behind this system, the weather will be quiet as we see split flow develop for the weekend that will transition to a very wavy pattern across North America next week. Highs will be back up around 40 for the weekend through Tuesday, with lows down around 30. Although there's little run-to-run consistency on any system around Thanksgiving, several of the models continue to show a stronger system developing in the central CONUS by the middle of next week, so that's something to keep an eye on if you have any travel plans around the holiday. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 537 AM CST Tue Nov 19 2019 LIFR conditions are present along and east of a frontal boundary currently in place from north to south through the center of the state. A narrow band of light precip was also slowly advancing east ahead of the front. LIFR/IFR conditions expected to continue this morning for STC, MSP, RNH, and EAU. Skies have cleared at MKT, with the cloud shield pushing just to the east. The same is true for RWF. However, MVFR stratus is certainly on the way from North Dakota and will fill in across western MN through the morning. MVFR area wide this afternoon and evening, a chance of clouds lifting to VFR levels overnight or tomorrow morning. KMSP...The edge of the stratus shield has made it farther east that previously expected, but latest satellite trends and hi-res guidance still offer confidence that the clearing will in fact remain to the west of MSP. /OUTLOOK FOR KMSP/ Wed...MVFR/IFR ceilings with -RA late. Wind SE 5-10 kts. Thu...MVFR/IFR likely. Chc -SN early. Wind NW 10-20 kts. Fri...VFR. Wind NW 5 kts becoming SW. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. && $$ SHORT TERM...SPD LONG TERM...MPG AVIATION...SPD