-- Discussion containing changed information from previous version are highlighted. --
508
FXUS63 KFGF 250900 CCA
AFDFGF

Area Forecast Discussion...CORRECTED
National Weather Service Grand Forks ND
400 AM CDT Tue Jun 25 2024

.KEY MESSAGES...

-- Changed Discussion --
- There is a level 1 out of 5 risk for severe thunderstorms over
  the Devils Lake basin Thursday evening, and a lower chance for
  severe thunderstorms elsewhere Thursday night into Friday.
-- End Changed Discussion --

&&

.DISCUSSION...
Issued at 356 AM CDT Tue Jun 25 2024

...Synopsis...

Westerly flow aloft is in place today, and while there will be a
series of progressive troughs and ridges, the main pattern will tend
to resemble zonal/quasi-zonal. Height falls behind the trough
passages should bring a period of below average temperatures at
times, though actual highs are complicated by timing of frontal
zones and precipitation in this pattern. There is strong
consensus regarding the mean evolution of the pattern, with
variance in the smaller details common to progressive patterns
like this.

...Today-Tonight...

The main frontal zone is almost completely out of our
area with much lower Tds and drier air aloft helping stabilize
conditions. However, near the frontal zone there is still an axis of
500-1000 J/KG elevated instability near the ND/SD through mid
morning which may support a few elevated showers/non severe
thunderstorms in our far southern RRV. Westerly BL flow ahead of the
next mid level wave keeps an axis of warm 850 temps in place so we
should see some recovery in temps (once again warmer than average),
despite the post frontal air mass in place. Lower Tds and marginal
lapse rates keep potential instability minimal in our area ahead of
this next shortwave rough later in the day. HREF supports a period
of elevated light showers (maybe a rumble of thunder) this evening
through Wednesday morning.

...Thursday-Friday Severe Threat/Rain...

A more organized trough develops
out of the Pacific northwest with a brief amplification of
shortwave ridging over the Northern Plains. This allows a period
of SW flow to build back into the northern plains. The warm
sector/instability axis favored to our west based on latest
ensemble clusters, and this region would favor initiation/better
severe potential. However, as the mid/upper trough moves east
Thursday this axis will begin to slide east and depending on the
timing, may support an elevated severe risk into our west
Thursday evening. Widespread showers/embedded thunderstorms then
overspread our region, while the frontal zone shifts south and
east through Friday. Depending on cloud cover/daytime
destabilization, this could act as a focus for new severe
thunderstorm development, but highly conditional on
clearing/frontal timing. GEFS CSU machine learning (and NBM
CWASP) highlight the low (5%) severe potential late Thursday
mainly in our west and in our far east-southeast Friday.

Regarding rain amounts: Within more organized convective elements
probs for 1"+ total rainfall will be expected with favored
region in global ensembles near the US/Canada border. There
isn`t currently a signal for more organized higher totals that
would create concerns for more than localized runoff issues.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1140 PM CDT Mon Jun 24 2024

VFR conditions prevail through the period at all TAF sites.
There is a low chance for isolated showers and thunderstorms
overnight; however, the cold front that previously brought these
storms into the area has moved south and east of the TAF sites.
Look for mainly clear skies and winds becoming more northerly to
northwesterly through the overnight period before increasing
heading into Tuesday mid morning.

&&

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

&&

$$

DISCUSSION...DJR
AVIATION...Lynch