Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/01/20
Area Forecast Discussion
National Weather Service Bismarck ND
850 PM CST Tue Dec 31 2019
.UPDATE...
Issued at 849 PM CST Tue Dec 31 2019
The forecast looks to be on track. Just waiting on precipitation
to start approaching northwest North Dakota in the next few hours.
UPDATE Issued at 527 PM CST Tue Dec 31 2019
No major changes were needed for this update. Just blended in the
latest observations of the sensible weather fields into the going
forecast.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 333 PM CST Tue Dec 31 2019
Quiet weather across the area this afternoon and evening as a weak
surface warm front nudges its way eastward across central North
Dakota. Temperatures this afternoon have struggled to warm ahead of
the front, and may see some daily highs occur after sunset east of
Highway 83 after the warm front passes through. A mid level
shortwave is moving along the Canadian border this afternoon, but is
only producing mid to high clouds.
A clipper system will move across southern Saskatchewan and Manitoba
tonight through Wednesday, and will be the primary feature of
interest for the short term period. An additional mid level
shortwave to the south of the clipper, along with low level warm air
advection, may lead to the development of light precipitation from
northwest into north central North Dakota late tonight. Model
soundings suggest this precipitation will fall in an environment
with maximum temperatures aloft anywhere from +1 to +4 C. The RAP
has been consistently warmer than other guidance. Therefore, with
surface temperatures below freezing, freezing rain, sleet, and snow
are all possible precipitation types through tonight. The QPF is
expected to be light, but could still see a few tenths of an inch of
snow and a thin layer of ice in some areas across northwest and
north central North Dakota through Wednesday morning, enough to make
surfaces slick.
A steady stream of mid level PVA will keep precipitation chances in
the forecast Wednesday afternoon. By this time, precipitation is
expected to be a rain/snow mix across the north and rain elsewhere
as most locations see highs above freezing under the warm sector of
the clipper.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 333 PM CST Tue Dec 31 2019
A cold front will move down from Canada Wednesday evening and into
the night. Chances for precipitation will mainly be confined along
the cold front Wednesday night, with rain/snow eventually changing
to all snow. Any accumulations should be light. There were previous
concerns for freezing drizzle potential behind the cold front late
Wednesday night. While there is certainly a loss of ice production
aloft, the current suite of guidance does not appear to contain
enough low level saturation and vertical lift to support freezing
drizzle, so will leave out of the forecast with this issuance.
Several clippers are forecast to move across the region through the
long term period. Temperatures will vary, but bitterly cold Arctic
air is expected to remain locked up in Canada. The first clipper to
arrive in the long term period is late Thursday into Friday. This
clipper will give us our best chance of accumulating snow. Only
expecting around 1-2 inches at this time, but there are some hints
in frontogenesis and EPV fields that mesoscale banding may be
possible.
After a brief period of ridging late Friday into Saturday, the next
clipper arrives late Saturday into Sunday. Most guidance keeps us
dry for this clipper passage, but winds look to be much stronger.
Depending on how temperatures impact the snowpack and additional
snowfall from now until then, cannot rule out some minor blowing
snow concerns on Sunday. Winds may reach headline criteria.
Another clipper or two look to move through early to mid next week,
but predictability decreases past this weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 527 PM CST Tue Dec 31 2019
VFR conditions are expected for the first few hours of the period.
However, a clipper system will enter the northwest overnight,
brining with it mainly MVFR ceilings and a mix of light snow,
freezing rain, and sleet across portions of the west and north. As
this precipitation spreads south and east, expect precipitation
to be either light rain and/or light snow by late Wednesday
morning and into the afternoon/evening hours. Southwesterly winds
will increase through the period with some gusts potentially
exceeding 20 knots across the west. Low level wind shear remains a
concern tonight and into Wednesday morning across the southwest
and south central.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ZH
SHORT TERM...Hollan
LONG TERM...Hollan
AVIATION...ZH