078 FXUS63 KMPX 090021 AAA AFDMPX Area Forecast Discussion...UPDATED National Weather Service Twin Cities/Chanhassen MN 621 PM CST Wed Jan 8 2020 .SHORT TERM...(This evening through Thursday night) Issued at 230 PM CST Wed Jan 8 2020 There remains enough consistency in the models to support at least drizzle/freezing drizzle, or occasional light snow/flurries across central Minnesota after midnight, and across east central/south central MN, and western Wisconsin Wednesday morning. The concern is the depth of the moisture which will correlate to the amount of QPF and whether ice crystal clouds are introduced into the atmospheric column. Although the GFS (vs the EC) has been more aggressive in terms of moisture, and QPF amounts, the latest run has also increased the moisture depth. The problem is whether the deeper moisture, which is currently across southern Texas, is quicker to advect across the Upper Midwest and allow for the atmospheric column to saturated faster by Wednesday. Upper level support remains conducive for large scale lift late tonight, and into Wednesday morning. Therefore, the concern is timing of the deeper moisture until the main upper level support moves off to the east by Wednesday afternoon. Although I do support that very light precipitation is likely across a good part of southern/eastern, and eastern MN, and adjacent WI, I don't support anything more than a hundredth or two of QPF over the eastern 1/4 of MPX CWA. The western 3/4 of MPX CWA will likely only see light precipitation but won't accumulate. The amount of ice crystals in the clouds will be concentrated across central Minnesota early Wednesday, and possible over eastern Mn, western Wi before 9 AM Wednesday. However, after 9 AM, most of the ice crystal clouds will be across northern Wi, limiting any snowfall to trace amounts at best. Due to the limited amount of QPF associated with the freezing precipitation, I am not expecting a significant impact to travel. Just be advised that if moisture is greater than forecast, QPF amounts will likely increase and begin to impact travel before temperatures rise above freezing. As with the previous forecast, temperatures will begin to rise overnight, with highs reaching the mid to upper 30s by morning in south central/east central Mn, and west central Wi, or before the cold front arrives in the afternoon. Farther to the west, temperatures will likely be reached earlier in the day with falling temperatures in the afternoon. No changes for Thursday night as the main system moves off to the northeast. .LONG TERM...(Friday through Wednesday) Issued at 230 PM CST Wed Jan 8 2020 Long term trends continue to indicate a rather progressive flow pattern through this period. Rather weak waves embedded in the faster flow aloft. Some small snow chances kept with the initial wave moving through the area Later Friday/Friday night mainly to the far southeast CWA as the main moisture and forcing remains well to the east. Cooling behind this system and timing of winds drops Saturday morning lows into the lower teens below zero over west central MN. We could see wind chills bottom out around 25 below for an hour or two there. Otherwise, the deterministic models diverge some on timing/handling the short waves moving through the area. The GFS is holding onto at least chance of light snow moving through the area Sunday/Sunday night. The ECMWF does bring a wave through but has limited moisture. A better chance of accumulating snow appears to arrive Monday night/Tuesday period with a stronger short wave. Both the deterministic models show this system moving through then. Following this system, the GFS continues to show some deepening of the western CONUS trough with colder air dropping south and east toward the upper midwest around midweek. The GFS is colder and a bit faster/deeper with this cold air intrusion. True arctic air arrives in with a progged 1047mb high pressure area nosing across the Dakotas and Minnesota. May be seeing more wind chill issues as the cold air arrives. Teens and perhaps some 20s below zero for actual air temepratures could arrive by next Thursday morning. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 621 PM CST Wed Jan 8 2020 Mid level clouds will persist through the evening, with lower clouds developing late tonight and into Thursday morning. Widespread freezing drizzle is likely to form over WI Thursday morning, with some areas extending into central and eastern MN as well. Introduced prevailing -FZDZ at RNH, with a PROB30 at STC, MSP and EAU. Temperatures should warm to near or just above freezing by afternoon, so the best chance for FZDZ will be late morning. Cigs may become IFR Thursday as well, especially before a cold frontal passage later in the day. KMSP...No concerns through tonight, but lower cigs will develop Thursday morning with pockets of freezing drizzle possible late morning and early afternoon. Ice accretion would be pretty light. Otherwise, light visibility reductions are likely due to mist. /OUTLOOK FOR KMSP/ Fri...VFR. Wind NW 5-10 kts. Sat...Mainly VFR. Chc -SN. Wind N-NE 5 kts. Sun...Mainly VFR. Chc -SN. Wind SE 5 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... WI...Winter Weather Advisory from 8 AM to 2 PM CST Thursday for WIZ016. MN...None. && $$ SHORT TERM...JLT LONG TERM...DWE AVIATION...BORGHOFF