Langdon, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

086
FXUS63 KFGF 221153
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
553 AM CST Sun Dec 22 2024

.KEY MESSAGES...

- Threat for a glaze of ice is lower and confined to far SE ND
  into parts of WC MN. WPC probs indicate 10-15 pct chance of
  0.01 inch or more Valley City area to Fergus Falls, mainly for
  this evening.

- Warming up for the holiday week.

&&

.DISCUSSION...
Issued at 316 AM CST Sun Dec 22 2024

...Synopsis...

Westerly flow at 500 mb today turns more southwest mid week and
southerly next weekend. One short wave to pass east-southeast
from southern Alberta into northeast SD tonight. Otherwise a
quiet period til next weekend.

...Today-Tonight...

Observations in Montana indicate a dry airmass in place just off
the surface and this seems to be limiting any freezing rain in
that area so far. Models do have it developing and over NE
Montana and far NW ND 12z-15z period. So a bit slower than prev
fcsts.

Overall theme from all the short term CAM models and global
models is for a weaker system at 500 mb moving ESE and only a
small area where enough moisture will be present with modest 700
mb frontogenesis to generate light precipitation. QPF amounts
and covearge of precip are significantly less than what was
shown 24 hours ago. Just north of the 500 mb vort will be an
area of light precipitation from NW ND into SE ND and central
MN. It does diminish as it moves into SE ND/MN tonight. BUFKIT
soundings focused near Lidgerwood ND in far SE ND indicate
a warm 850 mb layer late today as moisture tries to move in but
also sufficiently dry airmass 900 thru 750 mb. As 500 mb system
moves into NE SD sufficient moisture present to saturate the
900 to 750 mb layer 03z-06z and when that does temps cool and
the column is below zero. Thus would appear any fzra precip is
tied to early evening but when moisture is less....then
when moisture increases soundings favor more of a light snow.

WPC probs for 0.01 inch or more of freezing rain is 5-15 percent
from Valley City to Wahpeton to Fergus Falls....zero Devils Lake
to Grand Forks. NBM probs for same are under 10 pct in far SE ND
for this evening and LREF ensemble mean similar with probs for
glaze of ice less than 10 pct. With this will not re-issue SPS
as at this time doesnt seem warranted. Will message in HWO and
also continue a low chc freezing rain graphic and tailor it for
the WPC prob area 10-15 pct in far southern fcst area.

Of course...models and their ensembles may be off and if system
is back to being stronger than changes may be needed. But good
consitency from 00z data in the lesser impacts.


...Monday and beyond...

A dry period Monday thru Friday. Southerly surface-850 mb flow
takes over on Thursday the 26th and low level airmass moistens.
Wouldnt be too suprised to see some mist/drizzle at that time.
But predictability on that is low. NBM and ensembles from
GEFS/ECMWF keeping our area on the west side of any system
lifting north-northeast thru the western Great Lakes. Will use
model blend ptype which shows chc of fzra/ra Friday night and Saturday
RRV and east. Confidence as one would expect is very low in
this.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 549 AM CST Sun Dec 22 2024

12Z TAF forecasts are written and include a high degree of
uncertainity. Much of the stratocu clear is clearing out to th
east bringing clear. This in turn with light winds in ND ND
giving low cloud redevelopment and some fog. How all this
transpires the next 2-4 hours is uncertain. Fog and low clouds
may expand into DVL and GFK. Low clouds have expanded into GFK
but will fog? Fargo seems a bit safer to remain VFR this
morning. Bemidji AWOS and other state owned MN AWOS`s are not
transmitting out. This afternoon and evening also uncertain as
winds will be light/variable and pockets of low clouds, IFR and
MVFR will remain or return.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

$$

DISCUSSION...Riddle
AVIATION...Riddle