540 FXUS63 KFGF 191346 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 746 AM CST Tue Nov 19 2019 .UPDATE... Issued at 746 AM CST Tue Nov 19 2019 There is still light precip upstream of northwest MN in Canada that may continue to rotate south through the morning, however confidence isn't high in measurable. This still lines up with timing of slight chance/chance PoPs, and with temps above freezing expecting no impacts if there was additional rain (or a brief flurry). Light fog is lingering over northwest MN, however vis have been slowly improving and this may not last as long as some guidance had been indicating. Stratus lingering as expected, and the one short term forecast issue will be how warm we really get with thick cloud cover holding. Only minor adjustments made to near term trends at this time. && .SHORT TERM...(Today through Wednesday night) Issued at 410 AM CST Tue Nov 19 2019 Early this morning-Today: There is still weak energy rotating southeastward out of Canada, and this is supporting pockets of very light precip, low level moisture lingering over parts of northwest MN has supported fog development and patchy drizzle. Temps are generally above freezing, with a few locations in west central MN and southeast ND near or below freezing. Very isolated fzdz can't be completely rule out (localized travel impacts), but most precip should be just drizzle/light rain due to the milder lows. Expecting most precip to end during the morning hours, though a few sprinkle may linger through midday in northwest MN. Temps should warm up with another above normal day expected. Most locations should be near 40 in the Red River Valley and west (mid to upper 30s further east where there may be fewer breaks in clouds). Major focus of the forecast period is on potential winter weather event late tonight thorugh Wednesday night/early Thursday morning across eastern ND and northwest MN. Expecting travel impacts from potential accumulating snow or freezing drizzle. Evolution of positively tilted trough that will eventually slide over/east of our CWA is still consistent, however there is less confidence on evolution of an initial shortwave that rotates along eastern edge of this and the potential for several organized areas of strongly positive frontogenesis north of stalled frontal zone. Exact track and evolution of these mesoscale features still varies though the overall trend will be for them to track mainly north of Highway 200. How these develop will determine where axis of most accumulating snow will fall, and more intense banding associated with these features may support 4+" of snowfall over narrow areas. Ensembles still showing minimal clustering at the extremes and means fall generally in the 1-3" range across our north. Warm sector along frontal zone in our south and axis of WAA further complicate precip type, as moist early flow may keep lower levels saturated and where there isn't more organized banding/deeper moisture light freezing rain/freezing drizzle may occur at times during this event, with potential even further north as main snow bands wind down, but lower levels remain saturated. Along our far south temperatures may hold above freezing during the time of precipitation and any precip that occurs could remain just rain/drizzle. Though confidence is increasing in travel impacts for parts of our region, this is a low predictability forecast regarding snow amounts and precipitation type. Winds aren't going to be particularly strong (10-15 mph, gusts 20 mph at the highest end), so blsn is less of a concern. Still, where the banding occurs snow rates will be high enough for vis to drop near or less than 1/2sm at times. Ultimately I could see issuance of a Winter Weather Advisory for parts of our area due to a combination of impacts, but there is just too much uncertainty at this time. We will refine timing/location of precip and get a better handle on potential positions of higher snow rates/totals as we get closer to the event. .LONG TERM...(Thursday through Monday) Issued at 410 AM CST Tue Nov 19 2019 12Z Thu - 12Z Fri Positive tilted upper level trough moves across the area Thu. Low level cold air also moves across the area Thu/Thu night. Upper level ridging starts to move into the area Thu night with upper jet on the east periphery. Warm advection moves in from the west Thu night. Fri - Mon Longwave pattern de-amplifies during the period. Long wave trough broadens across the eastern US. Longwave ridge off the west coast retrograde farther west. Split flow will be across North America with northern stream across Canada and southern stream across the southern states. Operational models were already out of phase with the northern stream on Fri. The GFS ensemble mean was a little faster than the ECMWF ensemble mean on Fri then the ECMWF becomes faster than the GFS thereafter. Light rain or snow possible for Sun. Otherwise no significant weather is expected during this period. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 538 AM CST Tue Nov 19 2019 MVFR ceilings are prevailing across much of eastern ND, though there are a few VFR breaks in the larger area of overcast low stratus. IFR ceilings and fog are impacting much of northwest MN. Expect fog to lift during the morning hours, however low ceilings will tend to linger through much of the day. VFR may prevail for a period late this afternoon and evening in ND, however MVFR would redevelop as a system moves in from the west overnight tonight. IFR ceilings may continue through the end of the TAF period at KBJI, with less certainty at KTVF (may see MVFR for more of the day). As the system moves into the region tonight, light snow may begin to spread into KDVL or event KGFK by the end of the TAF period. Aviation impacts from snow and even the possibility for freezing drizzle increase during the day Wednesday across the region. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...DJR SHORT TERM...DJR LONG TERM...JH AVIATION...DJR