067 
FXUS63 KFGF 042245
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
545 PM CDT Tue Jun 4 2019

.MESOSCALE DISCUSSION...
Issued at 533 PM CDT Tue Jun 4 2019

Thunderstorms currently developing across the CWA this evening
along several remnant theta-e boundaries and an approaching cold 
front. MUCAPE values remain in the 1500 to 2500 J/Kg range across
much of the forecast area. We have been seeing updrafts regularly
reaching 50 dBz at the 30000 foot level with rapid developing 
cells this afternoon during peak heating. Several outflow 
boundaries are now in play and could cause constructive 
interference along the front and the aforementioned theta-a 
boundaries. 

The main risks for the remainder of the evening will be wind gusts
to 65 mph and half dollar sized hail as shear is expected to
further weaken. Activity is expected to diminish around 8 to 9 pm
with the potential for weak convection to continue thereafter. 

&&

.SHORT TERM...(This evening through Wednesday)
Issued at 310 PM CDT Tue Jun 4 2019

The severe weather threat tonight is the main forecast challenge.
At 3 pm the surface low was located over the northern Red River
Valley, with a cold front arcing back to the southwest from it. 
Showers and thunderstorms are trying to form along this boundary, 
mainly from central Cass County down toward south central North 
Dakota. In this area, temperatures are in the upper 80s with dew 
points in the middle 60s. Not a ton of bulk shear to work with and
the overnight convection did work the area over earlier. Some of 
the latest HRRR runs show thunderstorms breaking out over 
southeast North Dakota, but quickly exiting the FA by 6 to 7 pm. 
So confidence continues to decrease that much activity will form 
in this FA tonight. Once convection moves out of the area this 
evening, there could be a brief period of breezy northwest winds, 
but these should begin to decrease again after dark. In the wake 
of the cold front Wednesday, temperatures will be slightly cooler 
and humidity levels will be drier. Wind speeds also look quite a 
bit more variable.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 310 PM CDT Tue Jun 4 2019

Will remain in split flow Wednesday night into Thursday, with the 
northern stream branch driving short wave energy into the FA late 
Wednesday afternoon into Wednesday night. At the surface, it appears 
that convection will initiate over western North Dakota, then move 
east late Wednesday afternoon and Wednesday night. Models seem to 
show more activity over central North Dakota, potentially holding 
together but weakening as it shifts into this FA. Less certain about 
any precipitation in the Thursday through Friday time frame. 
Since the northern stream ridge axis crests over the FA, a dry 
scenario is more likely. Temperatures in the lower 80s on Thursday 
should jump more into the middle 80s on Friday.

Moving ahead into the upcoming weekend and into early next week, 
change is in order. A deep upper trough over the western United 
States pushes east, bringing cooler weather to the area. Similar to 
the past couple of days, there have been model differences on how 
fast any precipitation would work into the FA in this period. At 
this point, best agreement looks to be Saturday afternoon through 
Sunday. It looks a little drier Sunday night into Monday, but with 
the cold temperatures aloft and cyclonic flow, there could be some 
Monday afternoon instability showers around again. Like mentioned, 
it looks quite a bit cooler, with highs in the 70s by Sunday and 
Monday.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 129 PM CDT Tue Jun 4 2019

As mentioned in the update section above, there is now more
uncertainty with the potential storm development this afternoon.
For that reason, only mentioned VCTS in the TAFs. If something
develops and looks like it is heading for a TAF site, will amend
as need be. Ceilings in all the activity should remain in the VFR
range. Otherwise, still expecting winds to switch to the northwest
behind the cold front. These northwest winds may be a little gusty
at times into the early evening.


&&

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

$$

MESOSCALE...Lynch
SHORT TERM...Godon
LONG TERM...Godon
AVIATION...Godon