NWS Forecast Discussion

255
FXUS63 KMPX 171651
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1151 AM CDT Wed Jul 17 2024

.KEY MESSAGES...

- Quiet and pleasant the rest of the week with highs in the 70s.

- Highs in the 80s along with airmass thunderstorm chances return
  this weekend into next week.

&&

.DISCUSSION...
Issued at 334 AM CDT Wed Jul 17 2024

It`s a comfortable night with temperatures in the upper 50s to
low 60s and mostly clear skies. An upper trough axis will
pivot through the region this morning. This places a pretty
chilly airmass aloft overhead with 850mb temperatures around 8C.
A strong surface high pressure will build into the Upper
Midwest and usher in a stretch of pleasant weather over the next
few days. Highs will be on the cool side for July, only in the
low to mid 70s, but it`s a welcomed change after last week`s hot
and humid airmass. With dry air aloft, clear skies, and light
winds will allow temperatures to dip into the low to mid 50s
tonight and offer tired AC units an opportunity for a break.

For the rest of the week, we`ll continue to enjoy a rarity of
mild temperatures and low humidity. The culprit will be a slow
moving pattern dominated by amped flow aloft with an impressive
western ridge and stubborn trough over eastern NOAM. We`ll be
stuck in between with subsidence overhead west of the trough.
This is actually not a bad place to be for seasonable weather
conditions. This allows a surface high to settle overhead a few
days and tap into that colder continental air from northern
Canada, hence the forecast with highs in the low to mid 70s with
very comfortable dewpoints (40s and 50s) for the rest of the
week. Please find the time to get outdoors to enjoy the best the
warm season has to offer us in the Upper Midwest. Because we
all know what is waiting for us down the road in 3.5 months...

The weekend will offer a slight change up and guidance has
offered a wide array of possible outcomes from a little
precipitation to a wash out Saturday. Our upstream pattern to
the west will remain, but downstream our upper trough will shift
from the Great Lakes into far eastern NOAM. This will shift the
subsidence region out of the Upper Midwest and allow our
surface high pressure to wash out. This change will allow for a
return flow to develop, ushering in more moisture along with
southerly low level flow. This will allow highs to return into
the 80s, with dewpoints getting back into the low to mid 60s.
Add in the help from the cornbelt [evapotranspiration] and it`ll
be pretty warm and muggy. There will be chance for showers and
storms Saturday and Sunday, but the overall pattern doesn`t
appear to favor any potential severe thunderstorms, which is
always good news. There is always a certain amount of built in
uncertainty with amped patterns like this one so we`ll likely
begin to see the more realistic outcome for this weekend take
shape over the next day or so. Looking ahead to early next week,
we`ll see a gradual warm up with highs back in the low to mid
80s. Precipitation chances seem marginal as the upper flow
doesn`t evolve in a favorable manner to get meaningful weather
outside of airmass thunderstorms. There is a signal for the
return of mid to upper 80s for the second half of next week, but
there is also plenty of time for change considering it`s 10
days out. So if you`re not a fan of "cooler" summer weather,
give it a few days and you`ll be back to a more tradition warm
and muggy scenario!

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1146 AM CDT Wed Jul 17 2024

High pressure will result in north winds with occasional gusts
today that will go calm overnight, before becoming light south
to southwest directions on Thursday. Clouds will be of the
diurnal cu field variety, with lower cu coverage expected on
Thursday compared to what we are seeing today.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/
FRI...VFR. Wind SW 5-10 kts.
SAT...VFR. Wind SW 5 kts.
SUN...VFR. Chc for Sct aftn TSRA. Wind vrbl 5 kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...MPG

NWS MPX Office Area Forecast Discussion

Script by Ken True @Saratoga-Weather.org