Area Forecast Discussion Issued by NWS Grand Forks, ND
000
FXUS63 KFGF 181455
AFDFGF
Area Forecast Discussion
National Weather Service Grand Forks ND
955 AM CDT Mon Mar 18 2024
.KEY MESSAGES...
- Coord with BIS, near critical fire wx messaging in HWO for
much of E ND due to gusty SW winds and minimum relative
humidity values 25-35 percent.
- 60 percent chance of minor impacts due to snow accumulation
southeast North Dakota and parts of west central Minnesota
Thursday.
&&
.UPDATE...
Issued at 955 AM CDT Mon Mar 18 2024
It is actually pretty calm outdoors this morning and many areas
are seeing the sun. However, this is going to be short lived
again, with clouds already increasing across the FA. These
clouds are associated broad warm advection pushing from west to
east this morning. Expect these clouds to thin again by later
afternoon (North Dakota side) into the early evening (Minnesota
side). The calm winds this morning will increase during the
afternoon, becoming fairly gusty again by late afternoon into
the early evening. This period of gusty winds will overlap with
the decreasing clouds, but only for several hours. The end
result will be a fairly short window of near critical fire
weather conditions, more so across southeast North Dakota into
adjacent areas of west central Minnesota. Already have messaging
for this in the Hazardous Weather Outlook and a social media
graphic. But will keep an eye out for stronger than expected
winds or a drier than anticipated surge in the clearing later
this afternoon and early evening.
.UPDATE...
Issued at 652 AM CDT Mon Mar 18 2024
Stratocu clearing made it near Walker to Ottertail to Elbow Lake
MN and continues to move southeast. Skies mainly clear behind it
then there is some warm advection high clouds and a few mid
clouds moving east across central ND moving into E ND this
morning. Tweeked sky cover for this. Otherwise no changes.
&&
.DISCUSSION...
Issued at 323 AM CDT Mon Mar 18 2024
Stubborn stratocu holding on from International Falls thru
Bemidji to Wahpeton ND and points east. Slow clearing will
continue thru the early morning as sfc high pressure ridge which
is from near Winnipeg to Jamestown moves east. As it moves east
today, there will be a period of high level clouds in
association with 850 mb warm advection. This warm advection area
is due to a short wave that will be moving southeast into NW
Ontario. Gusty southwest winds will develop this afternoon south
central into northeast ND with gusts over 30 kts. RH values
mostly 30-35 percent in the windy zone enough to mention near
critical fire weather conditions in HWO, per coord with WFO BIS.
Tight temp gradient from east to west with 30s most of the day
in MN to 40s in E ND with a chance for low 50s west of Devils
Lake by mid aftn.
Cold front will drop south quickly tonight and a period of gusty
NNW winds overnight into Tuesday thru the area along with likely
stratocu and a chance for light snow/flurries. Did add pops in
for light snow late tonight thru Tues AM in the Red River valley
where short term models indicate some precip.
Quiet day on Wednesday as high pressure is over the area ahead
of the next weather system which will be over Montana.
For Thursday, models coming into good agreement in bringing a
500 mb short wave from southern British Columbia/northern
Washington state Wednesday east-southeast into far SE
ND/northeast SD/west central MN area by 00z Fri. 850-700 mb
frontogenetical forcing along with 850 mb warm advection look to
be the forcing mechanism to generate a snow band from north
central Montana into west central/northwest ND into southeast
ND/northeast SD into central or southern MN. NBM 4.1 probs for 2
and 4 inches or more of snow remain higher than
GEFS/ECMWF/Canadian ensembles and WPC experimental forecast
products. WPC indicates 20-30 pct chance of greater or equal to
4 inches of snow SE ND into parts of WC MN (along a Jamestown-
Wahpeton-Alexandria line) with GFS ensembles from 00z indicating
a 30 percent chance of the same and 12Z ECMWF ensembles
indicating less than 5 pct. Using QPF and snow ratio data from
WPC would indicate a 1-3 inch snowfall south of Devils Lake-
Grand Forks-Bemidji area with highest amounts closer to South
Dakota border. I did notice that trends for main frontogenetical
forcing from GFS is a tad farther south now than 24 hours ago.
Based on forcing a broad area of 1-3 inches with a narrow zone
of 4-5 seems most reasonable idea for upcoming event with that
narrow zone of higher amounts uncertain its its exact location
but favored far SE ND/NE SD/MN border area. The main snow is 12z
Thu to 00z Fri so a fast but quick hitting system.
Past the Thursday system we certainly look to remain active
with two more potential systems before the weekend ends. The
first being a weak clipper type system that looks to pass
through South Dakota with less than a 50% for greater than 1" of
snow from friday into Saturday. Warm air advection will be the
main driver with this wave though NBM members show support for
0.10-0.20" of QPF in the core of the band to the south and thus
the potential for higher totals should this system trend north
more into our region.
The second and potentially more impactful of the weekend systems
would be the result of west/southwest flow aloft by Sunday as we
find building ridging over the southeast US and digging troughing
out of the Rockies. Expected lee cyclogenesis in the high plains will
support a wide swath of snow across the area though there is
currently high spread in potential QPF totals and footprint at least
when looking just as eastern ND and northwest MN. Even when just
looking at the potential for > 0.25" of QPF one can find as high as
a 70% chance and as low as 20% for a FA max. This gives little
confidence in the eventual footprint though consistent signal from
all clusters producing > 0.25" at least in the vicinity of the
forecast area means it certainly bears watching with a close eye.
&&
.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 652 AM CDT Mon Mar 18 2024
Winds will turn to the southwest through the day with speeds
into the teens to low 20s by the afternoon with gusts well into
the 20s and low 30s particularly in northern areas including
KDVL, KGFK, KTVF after 18Z. Skies remain mostly clear with some
cirrus and scattered mid level clouds until tonight when a front
passes turning winds to the northwest while clouds move in and
drop CIGs to MVFR. Some flurries possible tomorrow morning but
confidence in timing and placement is currently low.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Godon
DISCUSSION...Riddle
AVIATION...TT