Casselton, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

173
FXUS63 KFGF 112340
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
640 PM CDT Sun May 11 2025

.KEY MESSAGES...

- A Red Flag Warning is in effect for critical fire weather in
  eastern North Dakota and northwest Minnesota this afternoon
  through Monday evening

- Near critical to critical fire weather conditions continue for
  Tuesday.

- Widespread rain Wednesday though Friday with a low (<5%)
  chance for severe weather.

&&

.UPDATE...
Issued at 640 PM CDT Sun May 11 2025

The greatest impacts from blowing dust though some minor
visibility reductions may still be ongoing until sunset. There
are still occasional gusts to 45 mph, so the wind advisory
continues. Our highs ended up near the 75th/90th percentile of
guidance with daily records broken at our main climate sites.
Very low RH values continue (10-15%) and critical fire weather
conditions will continue through the evening hours.

Very deep dry mixed layer is limiting instability locally over
much of our CWA, though there is enough elevated instability to
potentially support high based showers/storms holding together
as a weak wave moves to our northwest. Isolated dry
thunderstorms may move over the Devils Lake Basin through the
evening hours, with localized gusts and dry lightning the main
threats. Adjustments to near term trends the main focus of this
update.

&&

.DISCUSSION...
Issued at 241 PM CDT Sun May 11 2025

...Synopsis...

As a cutoff low central over Louisiana progresses east as it weakens
under the influence of central CONUS ridging to the north/west our
dominant upper riding across the northern plains will transition to
SW flow aloft. PNW troughing then migrates into the northern Rockies
with southerly moisture return building into the upper great lakes
states though westward is uncertain and may keep the critical fire
conditions in place further into the mid week that originally
expected. With the development of a surface low in the Dakotas by
mid day Wednesday rain is then forecast to overspread the region
Wednesday night through Friday with intermittent breaks/waves of
precipitation.

- Tuesday/Wednesday Thunderstorm Threat

In association with the incoming mid week system an EML atop sfc
frontal features will provide the ingredients for a low end severe
threat in the form of wind and hail. MLCAPE ~1000 J/kg and eff-shore
of 15-20kts atop what is likely to be deeply mixed boundary layer
(sfc to 850mb+). Overall with no SPC outlook thus far and the
parameter space would think it may be limited to a few marginally
severe storms. As for the general rain potential there is strong
signal for a widespread 0.25 to 0.50 (80% and 50% chance
respectively). With the inclusion of likley thunderstorms totals
exceeding 1.00 are entirely reasonable especially in more central
areas of North Dakota.

SEE FIRE WEATHER SECTION BELOW FOR FIRE DISCUSSION

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 640 PM CDT Sun May 11 2025

VFR conditions should prevail through the TAF period across
eastern ND and northwest MN, with the main uncertainty related
to blowing dust impacts during periods of stronger daytime winds
through this evening and again Monday when southerly winds
increase once again. Source regions will vary and we will
monitor/amend based on trends. Currently earlier dust impacts
have improved so I left mention of our TAFs for now. Wind shear
is still expected again tonight as a strong LLJ once again
redevelops.

&&

.FIRE WEATHER...
Issued at 320 AM CDT Sun May 11 2025

- Today/Tonight

RH currently is sitting widely below 15% in the Red
River Valley this afternoon as predicted and previously messaged.
Winds similarly while maybe a tad lower than expected are currently
20-25mph for most with a few upper 20s in southeast North Dakota.
Gusts have frequently been in the 30-40 range with a few over 40mph
leading to patchy blowing dust out there as evidenced by area
webcams presenting yet another hazard with the dry and windy
conditions. As the mixed layer continues to mix this afternoon RH
wont drop all that much more but could see another 2-3 points drop
before recover into the 30-40 percent range overnight. With winds
not dropping overnight it has been coordinated to maintain the Red
Flag Warning through the overnight despite the RH recovery as fuels
will remain dry and very susceptible to fire. RFW in effect through
15z Monday for this evening and poor overnight RH recovery.

- Monday

RH will begin the diurnal drop around 15/16z on Monday with a daily
min RH in the 15-20 percent range and winds of 20 to 25 mph and
gusts up to 40 mph more than capable of meeting critical fire
weather criteria through the evening. RFW in effect for 15z to
02z as RH falls below 20% and winds exceed 20mph with gusts
frequently over 30 mph.

- Tuesday

As the upper ridging begins to shift east the thermal ridging
becomes more diffuse allowing the PGF to relax reducing winds
slightly and seeing RH only bottom out in the lower 20s. Overall
considering critical fire weather conditions to still be on the
table but in a reduce spatial and temporal scale for Tuesday.
surrounding near critical messaging will also be needed across the
region. One thing to keep a close eye tuesday evening/night will be
an inverted trough that will 1) be the focus for some thunderstorm
activity in North Dakota but also 2) a wind shift as winds back from
the south to northeast/north in north central North Dakota.

Finally on Wednesday more widespread precipitation is expected to
overspread the region suppressing the fire threat for the near
term thereafter.

&&

.CLIMATE...
Issued at 243 PM CDT Sat May 10 2025

Record High Temperatures:

May 12 (Monday):
NWS FGF/UND: 95/1900
KGFK: 91/1977
KFAR: 96/1900
KPKD: 89/1906
KBDE: 85/1991

May 13 (Tuesday):
NWS FGF/UND: 92/1932
KGFK: 93/1977
KFAR: 95/1894
KPKD: 91/1900
KBDE: 88/1932

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Red Flag Warning until 9 PM CDT Monday for NDZ008-016-024-
     026>030-038-039-049-052>054.
     Wind Advisory until 9 PM CDT this evening for NDZ016-026>030-
     038-039-049-052>054.
     Red Flag Warning until 10 PM CDT this evening for NDZ006-007-
     014-015.
MN...Red Flag Warning until 9 PM CDT Monday for MNZ001>009-013>017-
     022>024-027>032-040.
     Wind Advisory until 9 PM CDT this evening for MNZ001>003-007-
     029.

&&

$$

UPDATE...DJR
DISCUSSION...TT
AVIATION...DJR
FIRE WEATHER...TT
CLIMATE...TT/DJR