403
FXUS63 KMPX 181200
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
700 AM CDT Tue Jun 18 2024

.KEY MESSAGES...

- Additional thunderstorms likely this afternoon and evening,
  some of which could be strong to severe with additional heavy
  rainfall.

- Locally heavy rain is still possible later today into tonight,
  however flash flooding is no longer expected to pose a
  widespread threat, prompting a cancellation of the Flood
  Watch.

- A brief break in the rain tomorrow should make for a nice day,
  before additional precip chances return Thursday through
  Saturday.

&&

.DISCUSSION...
Issued at 343 AM CDT Tue Jun 18 2024

Yesterday evening/night`s storms have progressed north of our area
this morning, allowing skies to begin clearing out. Increasing S/SE
low-level flow behind the northward advancing frontal boundary will
allow temperatures to rise into the low-mid 80s across much of the
area. Dewpoint temperatures in the low 70s will certainly make
things fell muggy again today, with heat indices potentially
creeping above the 90 mark. This will also depend on our cloud
cover, which the latest hi-res models suggest will fill back in
shortly after sunrise. Airmass destabilization will be the big
thing to watch today as we prep for another round of storms
along a passing cold front from the west.

A moderate to strongly unstable airmass with SBCAPE values of
2500+ J/kg would provide enough buoyancy for some robust
updrafts to form within an area of adequate deep-layer shear.
The primary threats will be damaging wind gusts and isolated
large hail along and ahead of the leading edge of the front
during the afternoon/evening when instability is maximized. As
previously noted, the relatively high low-level wind shear
warrants the need to watch for potential bowing structures as
the line comes together. Given its progressive nature, QPF
totals associated with the system look to most likely range from
0.5-1" with more localized amounts up to 2" possible. While
locally heavy rain is still possible through tonight, there is a
decreasing risk for widespread flash flooding potential,
prompting the cancellation of the Flood Watch for our central
Minnesota and western Wisconsin counties. Temperatures / dew
points will drop off pretty quickly behind the front, which
should feel nice after a muggy day!

Tomorrow should be nice day with highs generally in the
mid-70s, partly sunny skies, and relatively weak winds. Any
precipitation should stay southeast of our area as well, which
will allow for a nice break before rain chances return again on
Thursday. Southwest flow aloft will aid several more chances for
precip from Thursday through Saturday, with an additional 1-2"
of rain likely for most locations, and 4"+ still possible where
the strongest storms move through. Thus, continued surveillance
of rivers and streams for potential flooding concerns will be
needed through the end of the week.

A final kick from a h500 shortwave on Saturday should give way
to a more settled pattern at the start of next week, providing,
at the very least, a brief break in the active weather.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 638 AM CDT Tue Jun 18 2024

A line of weakening showers/storms is slowing tracking ENE
across portions of northwestern MN, which could impact AXN
within the next hour or so. The main story this morning will be
increasing southerly winds, generally persisting at 10-20kts and
gusting up to 30-35kts at times. They will gradually turn more
SW this afternoon ahead of an approaching cold front, which will
bring another round of showers/storms and a wind shift out of
the west. Some of these storms could produce severe wind gusts
and reduced visibility with heavy rainfall rates. Cigs will
generally be MVFR/VFR, with some periods of IFR possible as
storms move through the region.

KMSP...Expecting a gusty day, with strong winds around 45-50kts
just above the surface that could mix down during the
afternoon. Collaboration with ZMP led to increased confidence of
this potential, and have illustrated this in the latest TAF.
Later issuances may warrant a need for further increases in wind
speed/gust potential depending on how this morning plays out.
Confidence in TS development this afternoon has increased, with
the most likely onset around 22/23z. After the initial push of
heavy rain and strong gusts, lighter showers could persist into
the evening. Winds will quickly shift out of the west as the
front moves through, and then gradually turn more NW into the
night.

/OUTLOOK FOR KMSP/
WED PM...VFR/MVFR, chc -TSRA/-SHRA. Wind N 5-10kts.
THU...VFR/MVFR, chc -TSRA/-SHRA. Wind E 5-10kts.
FRI...VFR/MVFR, chc -TSRA/-SHRA. Wind S 10-15kts.

&&

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

&&

$$

DISCUSSION...BED
AVIATION...BED