694
FXUS63 KMPX 141114
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
614 AM CDT Sun Jul 14 2024

.KEY MESSAGES...

- Hot and humid continue with chances for strong to severe
  thunderstorms through Monday afternoon.

- Slight Risk (2 of 5) of Severe Weather today across western Minnesota.
  A Marginal Risk (1 of 5) for central/southern Minnesota and
  west central Wisconsin. The primary hazard will be damaging
  wind gusts.

- Cooler and drier pattern settles in Tuesday for the remainder of
  the week.

&&

.DISCUSSION...
Issued at 359 AM CDT Sun Jul 14 2024

Today through Monday... Satellite imagery reveals multiple mesoscale
convective systems across the Upper Midwest and northern Plains.
Radar reflectivity highlights the back edge of returns across west-
central Wisconsin thru SE Minnesota, marking the end of the evening
and overnight severe thunderstorm threat for E MN and W WI. These
storms produced a mixture of large hail and damaging winds across
central and eastern Minnesota before weakening after 7Z. The western
MCS over South Dakota prompted another severe thunderstorm watch
across SW MN has begun to lose steam as the outflow races ahead of
the convection. There has been a clear downward trend with this
structure that should mean the severe chances over W/SW MN are
trending down, too. This MCS had a history of producing 70-90 mph
wind gusts across central SD earlier tonight. There will likely be a
remnant MCV that could throw a wrench into our forecast for today.
It could help initiate storms across southern Minnesota later this
morning and suppress the warmer temps to our south.

Guidance favors a mostly dry forecast today but we shouldn`t
completely rule out a slight chance of some thunderstorm
development, especially in southern Minnesota. Latest CAM
guidance suggests we`ll still see highs in the mid to upper 80s
today with 90s possible in the inner Twin Cities and along I-90
in S MN, but there has been a clear trend to with lower dew
point temperatures this afternoon. This is good news for those
wanting to avoid low to mid 70 Tds. However, our Heat Advisory
for the Twin Cities metro has been cancelled as our heat index
values fail to meet the mid-90s threshold required. An
impressive amount of instability will build back in across the
Upper Midwest that`ll fuel another round of thunderstorms late
this evening into Monday morning. A shortwave trough will track
from south-central Canada into the northern Great lakes this
evening into Monday morning. These should bring upper level
support that promotes convection to our north and northwest.
Guidance favors an area of thunderstorms developing upstream
along and ahead of the sfc cold front across North Dakota this
evening. It tracks it southeast into Minnesota overnight into
Monday morning before exiting into La Crosse`s forecast area by
early Monday afternoon. There are other solutions that bring a
remnant MCV out of the Dakotas that is the focus point for
redevelopment late Monday morning into Monday afternoon across
portions of central Minnesota and NW Wisconsin.

This can`t be ruled out given how many MCS`s have moved through the
region over the past 36 hours. Sunday`s Slight Risk over W MN and
Monday`s Slight Risk over SE MN and W WI highlight the potential for
an MCS to impact W MN late tonight into Monday morning with damaging
winds as the primary hazard. While guidance supports this general
outcome, it`s unlikely that any CAM has the correct convective
evolution for this period. So expect something similar to Saturday
where we know we`ll likely have thunderstorms somewhere upstream,
but what they look like when they get here will wait to be seen.
Forecast soundings over W MN would support an initial wind threat
tonight before convection weakens further east. There is an
impressive amount of recovery through early Monday afternoon that
should support additional convection. MLCAPE values of 2500+ j/kg
with steep lapse rates and 30-40 kts effective shear should support
all hazards if convection can develop along the sfc cold front late
Monday into Monday afternoon. Any convection that can develop will
grow upscale fairly quickly. This will depend on what the timing of
the overnight MCS looks like. A slower, later arrival will likely
limit the potential for redevelopment and our main concern would be
reintensification of the decaying MCS. Highs will be in the low to
mid 80s Monday.

Tuesday through Saturday... A much cooler and drier airmass will
settle in on Tuesday and stick around through next Saturday.
Forecast high temperatures will be in the mid 70s to lower 80s.
Chances of precipitation remain low through Thursday night but end-
of-week shower chances do return Friday. Temperatures will begin to
warm up into next weekend with highs in the low to mid 80s, but
there is no real sign of another heat wave on the immediate
horizon.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 607 AM CDT Sun Jul 14 2024

Most CAMs are still insistent on a multi-hour period of MVFR
cigs developing over our WI terminals by mid-morning. This
should burn off by the early afternoon leaving predominantly VFR
area-wide for the remainder of the period. There is a chance of
a line of thunderstorms moving southeast from western to
southeastern MN overnight tonight so have added PROB30s for
-TSRA at all of our MN terminals. Winds will generally be light
out of the north-northwest today before slowing to calm/variable
tonight. Winds then become more southeasterly towards Monday
morning.

KMSP...Have added a PROB30 from 08-13Z Monday for a potential
line of thunderstorms passing through MSP.

/OUTLOOK FOR KMSP/
MON...VFR, CHC -TSRA/MVFR. Wind NW 5-10 kts.
TUE...VFR, Wind NW 5-10 kts.
WED...VFR, Wind N 5-10 kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...CTG