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Area forecast discussion
National Weather Service Grand Forks ND
1240 PM CDT Thu Sep 21 2017

issued at 1225 PM CDT Thu Sep 21 2017

Weak returns lifting north of the international border as upper
jet streak lifts northeast and low level jet becomes more focused
along the border. No changes necessary with temperatures on track.

Update issued at 924 am CDT Thu Sep 21 2017

Weak returns continue from the dvl basin into the northern valley
but not much for reports from obs or web cams. Because of this,
trimmed back on pops over this area. No other changes.

Update issued at 652 am CDT Thu Sep 21 2017

Regional radars continue to show a few echoes moving up toward the
Devils Lake region. Most of this is probably mid level clouds or
virga, as no metars are reporting anything. So there may be a few
sprinkles over there through the morning. Rest of forecast


Short term...(today and tonight)
issued at 336 am CDT Thu Sep 21 2017

The main forecast challenge will be severe weather chances over
the next couple of days. For today, there is a batch of mid level
clouds moving north-northeast out of northwest and north central
South Dakota. This is associated with the low level jet and warm advection.
This feature will continue to push north-northeast and may clip
the Devils Lake region with clouds and a shower during the
morning. Otherwise will see some gusty south winds again,
especially by late morning through the afternoon. Tonight the low
level jet will crank up once again, with decent focus into the
southern Red River valley and west central Minnesota, not so much further
north. Models differ exactly on how much thunderstorm activity
there will be, and where it will be. Storm Prediction Center has kept a marginal risk
for severe weather mainly east of a line from Lisbon to Hillsboro
to Baudette. Wpc has portions of this area in a marginal risk for
excessive rainfall. If strong to severe storms can get going, they
have the potential to produce heavy rain amounts. If they form
east of the forecast area or remain weak, that potential is low. The other
story will be the big northwest to southeast temp gradient

Long term...(friday through wednesday)
issued at 336 am CDT Thu Sep 21 2017

This large temp gradient will remain over the area Friday, with
the potential for 25 degrees of difference from northwest to
southeast. Of course, there is a frontal boundary that causes
that, and the front should be somewhere along a line from the
southern Red River valley up toward Baudette Minnesota by 7 PM Friday.
Models also show a weak sfc low over the southern Red River
valley. Again, quite a surge of moisture and shear. Low level jet
kicks in during the early to mid evening, and models seem to key
on this for the more rapid generation of storms. Therefore storms
may not be too widespread until late Fri afternoon into the early
evening. Then the activity continues through the evening and
overnight. Storm Prediction Center has the southern Red River valley into most of our
Minnesota forecast area in a slight risk for severe weather, while wpc has about the
same area in a marginal risk for excessive rainfall. So strong and
severe storms or training storms may produce a lot of rain.
Saturday into Sat night will be much cooler with rain chances

Sunday through Thursday...the active weather will continue
through the second half of the weekend as the area remains in
southwest flow aloft with an upper low out near The Four Corners
region and upper ridging across the eastern Continental U.S.. not much for
instability so expect mainly showers versus any thunder (although
a few rumbles, especially on the Minnesota side, not out of the
question). As the upper low gradually propagates north and east
across the area through the first half of the work week,
precipitation chances will finally begin to wane. Northwest flow
aloft will settle in by midweek with more scattered precipitation
chances, rather than widespread, through the end of the period.

Plenty of cloud cover through the first half of the week will keep
things quite cool with high temperatures generally only reaching
into the 50s. Decreasing moisture with hopefully more sun by midweek
should help push highs back into the 60s with seasonable lows in the
40s continuing.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1225 PM CDT Thu Sep 21 2017

Will see some mid cloud development over southern and eastern
areas later tonight as lift with low level jet and warm advection
organizes. Thunderstorms also possible but at this point
confidence not high enough to mention in taf. MVFR cigs also
possible tomorrow morning along and north of warm front which will
be lifting S-N from the southern fa.


Fgf watches/warnings/advisories...


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