681
FXUS63 KFGF 010443
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1143 PM CDT Tue Apr 30 2024

.KEY MESSAGES...

- Isolated thunderstorms in west central MN thru 02z.

- Next rain is Thursday, amounts 0.25 to 0.75 inch.

&&

.UPDATE...
Issued at 1139 PM CDT Tue Apr 30 2024

500 mb trough moving slowly north with one short wave near Grand
Forks and the other was moving into western Wisconsin. Area of
rain slowly moving north but has slowed down with rain centered
from Bemidji to Devils Lake and in this area rain amounts have
been the highest overall with amounts up toward 0.75 inch or
locally higher.


UPDATE
Issued at 717 PM CDT Tue Apr 30 2024

500 mb short wave is well defined and along the SD/MN border
between Sioux Falls and Watertown moving northeast. To the
north is the area of rain showers spreading north thru E ND and
NW MN. 500 mb short wave trough exists from main upper low in
southern Alberta thru south central ND to that short wave/vort
moving into MN. Surface trough located along this path as well.

This entire area of moisture is moving north- northeast. MU
CAPES in the 1000 j/kg south of the area along the SD/MN border
and in that area some sun occurred late in the day and temps
near 60 and just enough instability for a few storms to form.
They are moving not into WC MN lakes country. Not strong by any
means but enough for some rumbles of thunder. Rain amounts thru
00z in the 0.25 to 0.60 inch range thru the mid/south RRV and
into MN lakes country.

&&

.DISCUSSION...
Issued at 124 PM CDT Tue Apr 30 2024

Surface analysis indicates a weak surface low over the Dakotas, but
weakening thanks to a much faster deepening low over the Upper
Mississippi Valley. This will allow for the bulk of an unstable warm
sector to be isolated away from our area. However, lower level theta-
e advection may get far enough north to scrape our far southern
portions of the CWA. At this time, this appears to be a very low
likelihood as clearing is significantly limited thanks to the broad
swath of cloud cover across the Dakotas and given the 250mb jet max
is isolated well to the south of the area keeping the surface low in
South Dakota. Still, some elevated instability may provide a brief
risk for hail and low risk (20% chance) for thunderstorms. For this
reason, do not expect severe weather to develop later this afternoon.

Tomorrow will be drier as this system moves out. Relative humidity
values will fall into the 30s tomorrow, but recent rains should
limit the risk of fire spread. Additionally, wind speeds will remain
fairly benign with sustained winds up to 15 knots. Additional rain
chances will develop Wednesday night into Thursday, but the
probability of widespread impacts is low. The remainder of the
period will feature near normal temperatures with periodic chances
for rain once again. Freezing temperatures may arise late this
weekend but this will hinge on sub-synoptic scale things working
out.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1139 PM CDT Tue Apr 30 2024

Ceilings overnight into Wednesday morning will be an issue with
most locations dropping or maintaining in the IFR to low end
MVFR range. vsbys 3-5Sm in light rain/fog as well hanging on
esp Grand Forks to Devils Lake. Overall improvement anticipated
once we get past sunrise and can mix down some drier air and
clearing line moves more steadily northeast. That is the the
thought at least with VFR conditions spreading to most areas Wed
aftn.

&&

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

&&

$$

UPDATE...Riddle
DISCUSSION...Perroux
AVIATION...Riddle