083
FXUS63 KMPX 012103
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
403 PM CDT Mon Jul 1 2024

.KEY MESSAGES...

- Widespread showers and thunderstorms this evening through Tuesday.
Locally heavy rainfall possible, primarily across southern Minnesota &
western Wisconsin.

- Thunderstorms and locally heavy rainfall likely for the 4th of
  July

&&

.DISCUSSION...
Issued at 355 PM CDT Mon Jul 1 2024

Current observations across much of our sites reporting breezy
conditions out of the south-southeast ranging between 25-35 mph. Upper-
level cirrus continues to spread in overhead out ahead of our next
system that is approaching from the west. As mentioned in the previous
discussion, a strengthening low level jet is a likely culprit to the
showery activity beginning to show up on reflectivity early this
afternoon across eastern SD and western MN. So far though, most
rainfall does not appear to be reaching the ground likely due to dry
air within the boundary layer. Temperatures this afternoon will reach
the low to mid 70s.

Tonight, upper-level troughing as well as a strengthening jet streak
will reach the northern plains where WAA is strongest. Hi-Res forecast
soundings showing PWATs of rich Gulf moisture exceeding 1.8" well into
MN and WI. The convergence of these elements will create an environment
able to provide widespread showers and a few thunderstorms with locally
heavy rainfall possible. Current timing window for development occurs
this evening from west to east between 7-10 PM tonight. Although storms
are possible, the past few model runs bring the greatest severe threat
mainly across the Dakotas. However, a few storms in western MN could
produce isolated large hail and damaging wind gusts. Latest
forecasted QPF amounts through Tuesday morning show southeastern
MN and WI counties along and south of the I-94 corridor having
the greatest potential for observing between 1 to 1.25 inches of
rain. Farther north and west across eastern MN and counties
north of I-94 in WI could range between 0.75 inches to an 1
inch. Areas farther west can expect a half an inch or less.

The system will be slow to exit Tuesday morning to our west as a cold
front becomes occluded over northwestern MN. Therefore kept
chance PoPs for much of Tuesday especially for both east and
southern MN and western WI. Skies will gradually clear to where
some sunshine peaks through for parts of western MN tomorrow
afternoon. Tuesday`s highs temperatures will reach the lower 80s
and then upper 70s across western WI where cloud cover will be
more prevalent. Another shortwave associated with the larger
troughing pattern ejects late Tuesday afternoon and could
provide enough support for more showers/storm across
southeastern MN and western WI.

Wednesday will be warmer and potentially the nicest day of the entire
week. Flow will become zonal above surface high pressure. Skies are
forecast to be mostly clear with highs reaching the low to mid 80s.
Thursday, a developing wave over the PacNorthwest is progged to
strengthen over the upper midwest Thursday afternoon. We dont
want to put any rain on the firework fuses but ensemble guidance
isn`t giving us many "oohs or ahs" to marvel over in terms of
dry conditions. NBM guidance continuing to show likely PoPs
across much of upper midwest through the afternoon/evening
hours. Ensemble guidance continues to hint at heavy rain
potential with QPF amounts nearing an inch. Rain chances
continue into the weekend however coverage will not be as
widespread and heavy rain threats look to decrease. &&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 123 PM CDT Mon Jul 1 2024

VFR with MVFR/IFR SHRA/TSRA likely late this evening into
tonight through tomorrow morning. Scattered to broken ceilings
are beginning to make their way into western MN this afternoon
out ahead of our next system that will provide SHRA/TSRA across
all terminals tonight from west to east. Breezy SSE`ly winds
will range between 20- 30kts this afternoon before weakening
some to 15-25kts overnight. IFR stratus is likely along with
trailing scattered -SHRA in wake of the passing system. Winds
will shift to SW and not as strong between 10- 15kts tomorrow
morning although cigs reluctant to budge out of IFR categories
for the remainder of the TAF period.

KMSP...VFR to start then transitioning to MVFR to IFR categories overnight as
-SHRA/TSRA arrive. Current hi-res guidance looks to have SHRA
 encroach on MSP as early as 2z with storms likely between 4 to
 8z. Scattered SHRA is possible in wake of the system passing
 until about 12z. Low MVFR/IFR cigs will remain in place through
 the rest of the period. SSE`ly winds remaining breezy this
 afternoon with gusts nearing 30kts but should begin to decrease
 after sunset to near 20kts. Winds shift and decrease between
 10-15kts out of the SW late tomorrow morning. A slight chance
 for -TSRA was hinted in the guidance late afternoon hence the
 PROB30 from 22/24z.

/OUTLOOK FOR KMSP/
WED...VFR.Wind WSW M10-15G20 kts.
THU...VFR. PM MVFR SHRA/TSRA.Wind SE 5-10 kts
FRI...MVFR SHRA/TSRA lkly. Wind NE 5-10 G15-20

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

$$

DISCUSSION...Dunleavy
AVIATION...Dunleavy