Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KFGF 200548
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1148 PM CST Mon Feb 19 2018

.UPDATE...
Issued at 1148 PM CST Mon Feb 19 2018

Tweaked POPs a bit for current radar trends. More snow continues
to come in from the southwest, with activity over eastern SD
seeming on a good track for our southeastern counties. Even more
further upstream, so will keep categoricals going. Will continue
to keep 4 to 6 inches snow totals in that area.


&&

.SHORT TERM...(This evening through Tuesday)
Issued at 325 PM CST Mon Feb 19 2018

Not much change for this forecast period from our previous
package. Some light snow or flurries continue to brush some of
our westcentral MN counties this afternoon while clouds thicken
and lower over southeast ND... in advance of a more significant
moisture surge still working its way up through central SD. A hint
of the likely deformation band is currently setting up in an arc
from northeast SD into westcentral MN.

Model guidance is fairly consistent on placing band of QPF over
the tri-state border area in the 0.25 to 0.40 inch range. With
snow ratios likely to push from 18:1 to 22:1 through the period
there should be an area pushing 6 inches of snow or a bit more,
from near Aberdeen... through Fergus Falls... and past Park
Rapids. Heaviest snowfall there links peak moisture advection
with coolest boundary layer temps... from just after midnight
through Tuesday morning drive time.

For now... its looks as if the Lisbon-Fargo-Bemidji Line is
setting up as the north edge of that heavier (3 to 5 inch)
snowfall range, with snowfall likely to taper off fairly sharply
north of that line. Will remain to be seen if the heavier snow
band shifts further north as some of the HRRR runs show a bit of
variability. Thus have stuck with previous Winter Weather Advisory
outline and timing, but have split out the southern portion to
indicate the somewhat higher snowfall potential there.

System exits the area a bit more slowly on Tuesday than the
previous system, so some lingering low clouds and snow flurries
are likely after midday. Northwest winds will increase in the
late forenoon and afternoon, so some blowing and drifting is to
be expected in open areas.

.LONG TERM...(Tuesday night through Monday)
Issued at 325 PM CST Mon Feb 19 2018

Clearing skies and fresh snow will lead to a cold night on Tuesday
with dangerous wind chills. After this cold night a warming trend is
present through Sunday, with temperatures from Thursday through the
weekend temperatures near normal.

High pressure dominates until Thursday when the next chance for snow
arrives. An upper level trough and its associated surface low will
provide some light accumulating snow. There is fairly good agreement
between the GFS and ECMWF for this event. The best snow chances will
be from southeast North Dakota to north central Minnesota. High
pressure returns Friday into the weekend. There is still a clipper
passing nearby in the GFS in around Sunday but the ECMWF and CMC
have a different evolution in this period so there is significant
uncertainty.

&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1148 PM CST Mon Feb 19 2018

Snow moving in has brought visibility down to the 2 to 5SM range,
although sometimes down to 1SM or less. Ceilings have been mostly
VFR although some spots are down to MVFR. This trend will continue
with a few breaks in the snowfall allowing visibility to come up,
but then another round bringing them back down again towards
tomorrow morning. The snow will move off to the northeast by
afternoon and all sites will become VFR by the end of the period.
Winds at 10 to 15 kts will start out of the north, then become
more northwesterly and then westerly by tomorrow evening.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Winter Weather Advisory until noon CST Tuesday for NDZ038-039-
     049-052-053.

MN...Winter Weather Advisory until noon CST Tuesday for MNZ002-003-
     009-015>017-022>024-027>032-040.

&&

$$

UPDATE...JR
SHORT TERM...Gust
LONG TERM...NC
AVIATION...JR


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.