Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/05/20

Area Forecast Discussion
National Weather Service Marquette MI
544 PM EST Wed Nov 4 2020 .SHORT TERM...(This evening through Thursday) Issued at 358 PM EST WED NOV 4 2020 WV imagery and RAP analysis indicated a mainly zonal pattern across southern Canada and the northern CONUS. Shortwave troughs were located over far nw Ontario and over southern Saskatchewan. At the surface, low pressure over northwest Ontario was dragging a weak trough into northwest MN while a cold front lagged over southern Manitoba. Brisk southwest flow prevailed across Upper Michigan between the low and high pressure over the Ohio Valley. Tonight, expect the trough to move through and cold front to move through Upper Michigan tonight with winds veering westerly. Little more than a band of mid clouds or cirrus will move through late given the very dry conditions through the region. Enough boundary layer mixing should prevail to keep temps dropping below the upper 30s inland while downslope flow maintains temps int the mid 40s north central near Lake Superior. Thursday, even with 900 mb temps dropping to around 7C behind the front (around inland mixed layer heights) temps will remain well above seasonal averages. Again boosted forecast max readings closer to the model 90 percentile. Temps should range from the low to mid 60s south to the mid 50s north, with some onshore cooling from Lake Superior. .LONG TERM...(Thursday night through Wednesday) Issued at 430 PM EST WED NOV 4 2020 Dry and warm conditions will continue until the beginning of next week, as the temperature inversion and low level dry layer look to stay in place. Come Monday, a cold front will move through the area slowly, eroding the dry layer and bringing rainfall to Upper Michigan. As this cold front tracks through our area, look for temperatures to cool enough to see some snow possible on the backside of the cold front in the west. Also, there appears to be a low pressure moving through our area Wednesday, which looks to bring more mixed precipitation back into our area late in the forecast period. Further details are below. The jet stream will be too far north for us to be affected by a shortwave that will move through northern Ontario Thursday night and Friday. The jet stream will, however, dip over the western US during that time period, allowing for cyclogenesis to occur and thus the creation of a synoptic low. This synoptic low looks to develop a warm front over northern Ontario Friday night/Saturday. This front looks to bring cloud cover and waa over the U.P.. As the warm front moves north and the cold front approaches from the west Sunday, expect stronger southerly winds. The NAEFS and ENS have winds in the 90th percentile from Sunday night into Monday night. Therefore, winds could very easily be stronger than what the NBM was placing in the grids for Sunday and Monday. However, there was not enough confidence to include these higher numbers in the grids; just something to keep an eye over the course of the next few days. As the cold front moves through Sunday night into Monday night/Tuesday, heavy rainfall may be possible, as PWaTs look to be in the 97.5th percentile according to the NAEFS and ENS. On top of this, mid and upper level winds look to be in the 90th percentile as the cold front moves through, hinting at highly favorable conditions for parcel uplift. At the back end of the cold front, snow will look to mix in, particularly over the west, as temperatures will have cooled. As the cold front finishes moving through the area Tuesday, look for another low pressure to develop in the southern Rockies and quickly lift northeast. It looks to move through our area Tuesday night/Wednesday morning, and with it bring rain and snow over the Upper Peninsula, with more snow west and more rain east. Expect precipitation chances to diminish over the daytime hours Wednesday. A final note worth mentioning is that temperatures for the early part of the extended period look to be exceedingly warm. NAEFS and ENS have max temperatures in the 90th percentile at the 850 mb level. That, and the waa associated with the warm front/ahead of the cold front may bump up temperatures further than what is currently in the grids. Also max temperatures may be higher Monday; however, given that there was a difference in model guidance for Monday temperatures, decided not to change increase the temperatures from the NBM. It is all dependent on how strong the waa is ahead of the cold front. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 544 PM EST WED NOV 4 2020 Expect VFR conditions through the forecat period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 358 PM EST WED NOV 4 2020 SW winds could reach 20 kts ahead of a cold front, then veer west and then NW Thursday morning behind the front before diminishing to less than 20 kts on Thursday. Winds should then remain at or below 20 knots through Sunday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...TAP AVIATION...07 MARINE...JLB