Scientific Forecaster Discussion
fxus63 kfgf 181456
Area forecast discussion
National Weather Service Grand Forks ND
956 am CDT Wed Sep 18 2019
issued at 955 am CDT Wed Sep 18 2019
Upper level low pressure system was located over north central ND
and was moving to the northeast about 25 knots. Also radar indicated
showers/thunder over north central ND along the international
border. Precip was moving east about 25 knots. Going forecast looks
good. No changes at this update.
Update issued at 642 am CDT Wed Sep 18 2019
Showers exiting the Baudette area so after 13z fcst area is dry.
Watching the shoers and tstorms moving east on the south side of
the upper low. There is a risk of some of these to reach the far
northwest fcst area this morning as the low moves northeast. Moisture
will also move east around the low and cloud cover will likely
affect northern fcst area as we go thru the day with 850 mb
moisture lingering into tonight in northwest Minnesota and far NE ND. Will
maintain the risk of a shower or T-storm midday and aftn near the
Canadian border. Windy still looks good with gusts 30-35 kts in
the dvl basin.
Short term...(today and tonight)
issued at 328 am CDT Wed Sep 18 2019
At 08z, sfc low near the Estevan sk region with 500 mb low moving
north-northeast thru western ND. Area of T-storms formed in the axis of the
45-50 kt low level jet in eastern South Dakota prior to 05z and motion has
been almost due north with T-storms moving thru wrn Minnesota and far southeast
ND with showers up thru Fargo area. Area of precipitation has been
farther west than earlier short term models indicated. Activity
will exit northwest Minnesota this morning by 14z, but will continue to update
pops as needed.
Once this activity moves out a fairly quiet day, albeit windy one
as 500 mb low and sfc low move north-northeast into western
Manitoba and gusty west winds move in. Mixed layer winds in the
35 kt range midday and aftn Wednesday...with sustained values in
the 20 kt range. Therefore just shy of Wind Advisory criteria.
Also expect a good deal of clouds wrapping back east on the south
side of the system thru northern fcst area. Also a small chc for a
shower/T-storm midday/aftn along Canadian border.
Tonight will see continued clouds move across the nrn fcst area
before clearing out late night as upper low continues to move
northeast. Winds diminishing.
Long term...(thursday through tuesday)
issued at 328 am CDT Wed Sep 18 2019
A quiet day Thursday daytime with dry conditions expected and
winds returning to the southeast direction. Continued warm with
highs 70s to around 80.
The redevelopment of the central Continental U.S. Upper ridge promotes the
advection of moisture and warmth over the Dakotas Thursday and
Friday. This comes ahead of another shortwave trough moving out of
the northern rockies into the Dakotas. This trough focuses forcing
for ascent in tandem with a cold front to move through the region
around Friday promoting the development of thunderstorm. The air
mass progged to move over the region ahead of the trough will be
comprised of relatively high moisture content adding to instability.
This along with increasing winds ahead of the trough brings the
chance for strong to perhaps severe storms late Thursday as well as
Friday. Due to the high moisture content feeding into this system,
the threat for excessive rainfall also exists. Temperatures Thursday
and Friday will be unseasonably warm with highs into the 80s.
The trough exits the region Saturday with breezy westerly winds and
lingering rain showers early. Beyond Saturday, zonal to northwest
flow aloft allows temperatures to trend closer towards normal, ie
lows in the 40s/50s and highs in the 60s/70s. While the trend
towards drier conditions looks favorable early next week, there
still remains the chance for at least a shot of rain with any
Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 642 am CDT Wed Sep 18 2019
Clouds exiting the far eastern fcst area thru 15z leaving a mostly
clear sky with some cirrus over most of the fcst area but watching
clouds move east on the south side of the upper low and these will
move into dvl basin later this morning and then across the nrn Red River
and northwest Minnesota. Risk of MVFR cigs, but likey more lower end VFR.