764
FXUS63 KMPX 070848
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
348 AM CDT Tue May 7 2024

.KEY MESSAGES...

- Showers & a few rumbles of thunder continue this morning
  across eastern Minnesota & western Wisconsin.

- Scattered thunderstorms redevelop this afternoon & evening
  across far-eastern Minnesota & western Wisconsin. A few strong
  storms are possible.

- Another round of thunderstorms & locally heavy rain is
  expected Wednesday night across far-southern Minnesota.

&&

.DISCUSSION...
Issued at 313 AM CDT Tue May 7 2024

The line of showers & thunderstorms moving east out of western
Minnesota continues to weaken overnight, with only a few
sporadic lightning strikes remaining. These rain showers will
continue to move east across eastern Minnesota * western
Wisconsin into the morning with rainfall amounts generally
remaining less than 0.25".

ANother round of scattered showers & thunderstorms is likely
later this afternoon & evening, as the surface boundary
responsible for the current precipitation occludes & stalls out
over far-eastern Minnesota & western Wisconsin. Upper level
support arrives later this afternoon in the form of a lobe of
vorticity pivoting around the upper level low to our west, which
should generate enough lift to generate scattered showers &
thunderstorms along & ahead of the stalled-out surface boundary.
One concern is that cloud cover from this morning`s rain will be
slow to clear out this afternoon & reduce instability for
thunderstorms this afternoon & evening. However, this most
likelywould just limit the potential for any strong to severe
thunderstorms, & at least a few showers/storms are still likely
to develop. If we are able to maximize the instability this
afternoon, mixed-later CAPE values approaching 1000 J/kg &
effective bulk shear of 25-30 kts could support a few organized
storms, capable of small hail & brief gusty winds. Rainfall
amounts will be spotty given the scattered nature of the
showers, but amounts near 0.5" are possible wherever it does
rain later today, with the chances for more widespread rain
increasing as one goes farther east into Wisconsin.

The pattern remains active Late Wednesday into Thursday as the
upper-level low lingers over the northern plains & continues to
pivot lobes of vorticity over the region. The most pronounced
one of these comes Wednesday evening into Thursday morning over
far-southern Minnesota, where multiple rounds of slow-moving
thunderstorms are likely along a surface trough extending
northwest from the surface low lover the mid-Mississippi
Valley. Ensemble guidance shows some outlier solutions towards
heavy rain but this signal is highly evident on the higher
resolution convective-allowing models, where most of them
depict localized rainfall amounts of 3-5" somewhere across far-
southern Minnesota/northern Iowa/eastern South Dakota.
Obviously our confidence remains low on where exactly this heavy
rain could fall, but it`s presence on multiple CAMs means we`ll
have a heavy rain/flooding threat to keep an eye on Wednesday
night. A few strong thunderstorms are likely as well in addition
to the heavy rain potential.

The pattern generally dries out for the latter half of the week
& into the weekend,as the remnants of the upper level low
dissipate & drier northwest flow develops aloft. isolated
diurnally-driven showers can`t be ruled out with any weak lobes
of vorticity embedded with the flow, but these 10-20% PoPs
aren`t much higher than the background average changes for rain
in early May. temperatures will be seasonable through the
weekend wit afternoon highs generally in the upper 60s to low
70s. A trend towards warmer temperatures looks likely next week
as heights gradually rise over the region.


&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 1109 PM CDT Mon May 6 2024

VFR conditions will transition to MVFR/IFR as a line of showers
with a few embedded thunderstorms moves across the region
affecting all TAF sites. Winds will be southeast ahead of this
line of precipitation, but then become more southerly and
eventually southwest late Tuesday into Tuesday evening. There is
another chance for thunderstorms to develop Tuesday afternoon
and evening at KMSP, KRNH, and KEAU.

KMSP...Showers and thunderstorms will move through after
midnight tonight, and exit Tuesday morning. One change from the
previous forecast is that confidence is increasing that showers
and thunderstorms will develop again Tuesday afternoon and
evening. A few could produce gusty winds and small hail.

/OUTLOOK FOR KMSP/
WED...Mainly VFR. Chance MVFR/-TSRA late. Wind NE 10-15 kts.
THU...VFR. Wind NE 15-20G25-30 kts.
FRI...Mainly VFR. Chance PM MVFR/-TSRA. Wind W 10-15 kts.

&&

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

&&

$$

DISCUSSION...ETA
AVIATION...JRB