664 FXUS63 KFGF 082120 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 320 PM CST Fri Mar 8 2019 .SHORT TERM...(This evening through Saturday night) Issued at 320 PM CST Fri Mar 8 2019 The main change with this update is the north-northwestward nudge of the main precipitation area for Saturday/Saturday night's storm system. An upper level trough will move out of the 4-corners region tonight and into the plains states tomorrow. Snow and perhaps a bit of freezing drizzle will begin in SE ND late tonight/early tomorrow morning. The snow will be heavy at times, with 6-12 inches possible across southeastern ND and into much of NW MN. The 12Z NAM was further to the NW than other runs...pushing the frontogenesis as far west as Grand Forks to Roseau. Other models are more to the east. However, 6" of snow looks quite reasonable for the Grand Forks area, and so have expanded warning northwestward a bit. Given the frontogenesis...over 12" will be possible somewhere in the warning area...but that won't be exactly known until we get closer to the event. NAM bufr has 25 kts gusting to 35 kts at GFK and FAR on Saturday night...raising the concern for blowing snow a little higher than before. Have bumped up winds slightly to account for this. If the NAM solution continues to look true...the winds could linger deep into Sunday morning. So, generally, from southeast of a line from Lake of the Woods to SE ND...6-12" of snow is likely...with 12-18" possible in a small area. More details will be known down the road. .LONG TERM...(Sunday through Friday) Issued at 233 PM CST Fri Mar 8 2019 Models in general agreement this run and will go with a blended solution at this time. Focus is on a system expected to impact the forecast area around mid week. For Sunday into Sunday night...The main upper low moves into the Great Lakes with a fairly tight surface pressure gradient remaining over the the valley and east...with snow tapering off ahead of surface high pressure settling over the region. By Monday into early Tuesday...surface high pressure remains in control across the region. The upper ridge is forecast to rebound with thickness values indicating above freezing temperatures over the area ahead of the next system. For Tuesday through Friday...another system is forecast to develop across the central Plains. At this point...the general trend is for a Colorado low to develop late Tuesday and track northeastward across eastern Nebraska into Wisconsin through the period. Abundant moisture will accompany the system as the Gulf opens up and a strong low level jet transports moisture into the upper Mississippi valley. Considering the warming indicated ahead of the system...some freezing precipitation cannot be ruled out...mainly across the Minnesota zones...but will keep out of the grids for now until confidence increases. As the system continues to move toward the western Great Lakes and departs...will see cooler temps as precipitation tapers off to end the period. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1120 AM CST Fri Mar 8 2019 Latest TAFs reflect battle between IFR and MVFR cigs/vis today. All and all will see a slight improvement today but conditions deteriorate tonight, especially late. Not included in any TAFs is the possibility for FZDZ late tonight. Best chance appears to be from FAR to BJI and south between 06Z and 12Z. Otherwise, snow moves in shortly thereafter and will likely be heavy at times at FAR and BJI...with the potential for very poor conditions extending to GFK and TVF depending the track of the low. All locations will see some snow, but the worst of the five TAF sites will be FAR and BJI. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Winter Storm Warning from 6 AM CST Saturday to 1 PM CDT Sunday for NDZ028>030-038-039-049-052-053. Winter Weather Advisory from noon CST Saturday to 1 PM CDT Sunday for NDZ008-014>016-024-026-027-054. MN...Winter Storm Warning from 6 AM CST Saturday to 1 PM CDT Sunday for MNZ003-029-030-040. Winter Storm Warning from noon CST Saturday to 1 PM CDT Sunday for MNZ002-015>017-022>024-027-028-031-032. Winter Weather Advisory from noon CST Saturday to 1 PM CDT Sunday for MNZ001-004>009-013-014. && $$ SHORT TERM...Knutsvig LONG TERM...Hopkins AVIATION...Knutsvig