Area Forecast Discussion
Issued by NWS Grand Forks, ND

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FXUS63 KFGF 211739

Area Forecast Discussion
National Weather Service Grand Forks ND
1239 PM CDT Wed Mar 21 2018

Issued at 1236 PM CDT Wed Mar 21 2018

Area of light snow between Grand Forks and Bemidji is slowly
weakening and vort max as identified on water vapor is weakening.
Will continue to lower pops thru the aftn as area dwindles and
slowly moves east. Some clearing entering the far west fcst mainly
just west and south of Devils Lake. But do expect widespread low
clouds to re-develop overnight along with risk of fog, highest
risk west of the RRV.


.SHORT TERM...(Today and tonight)
Issued at 356 AM CDT Wed Mar 21 2018

Upper level ridge builds over the Rockies today and tonight. Flow
aloft becomes more northwest aloft with time. Water vapor loop
indicated two short waves. One was located over eastern ND and the
other short wave was over western ND.

Cross section indicated some drying aloft occurs above 850 hpa from
the west during the day today. A wind shift line as located in
western ND. Some warm advection was occurring at low levels east of
a wind shift line. Low level instability will shift across the area
today. Light precip was occuring in the low level instability.
Precip will shift east across the area through this evening.

.LONG TERM...(Thursday through Tuesday)
Issued at 356 AM CDT Wed Mar 21 2018

Thursday...This will be the calm before the storm with northwest
flow aloft and surface high pressure moving east. Temps should be
near to slightly above seasonal normals in the mid 30s to low 40s.

Friday and Saturday...Models continue to indicate some signficant
precipitation moving into the region as a shortwave comes over the
top of a ridge and into the Daktoas on Friday. NAEFS percentiles
continue to show 99 percentile or more for PWATs and QPF. Still
quite a bit of spread among the GEFS plumes for QPF, ranging from a
quarter inch to an inch of liquid for FAR, but good indication of
some significant precip across the area. The GFS shows some
indication of frontogenesis and banding potential which fits with
high QPF values. Southeast winds and a lot of moisture should keep
diurnal temperature range Thursday night into Friday fairly small,
which will have an impact on precip type. So will the timing, which
as of current runs have the precip moving in during the afternoon on
Friday, with some higher QPF values lingering into Friday evening.
Depending on how heavy snow is as it falls, some melting could occur
as it falls. Still a high level of uncertainty as to how this will
play out, but will put out an SPS highlighting the system and
potential for high impacts. Precip will taper off during the day on
Saturday as the shortwave moves east.

Sunday through Tuesday...An active pattern continues with
southwesterly flow aloft and several shortwaves moving through. Some
variation on timing between model runs, but right now it seems that
the next shortwave will be moving in late Saturday night into
Sunday, with models again showing a decent amount of QPF. Precip
type is again uncertain especially during daytime hours with
melting, but another few inches will be possible. Yet another
shortwave will move through Monday before a bit of a break for


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1236 PM CDT Wed Mar 21 2018

Most areas to remain in IFR or low end MVFR conditions in
cigs/vsbys thru 18z Thursday.  Light winds.




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