625
FXUS63 KMPX 170544
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1244 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 126 PM CDT Tue Jul 16 2024

h5 analysis this afternoon shows an upper low over northwest
Ontario, with a positively tilted trough extending southwest
from it into the Dakotas. Lift from mid and upper level speed
maxes along this trough, in addition to steep low level lapse
rates from daytime heating has been just enough to generate some
isolated showers. Forecast soundings show a warm nose around
around h6 that is effectively capping how deep this convection
goes, so the ceiling for what showers will be able to do today
is pretty low, with the vast majority of our area remaining dry.
This isolated shower activity will sag south with the trough
through the afternoon, with activity quickly diminishing with
the setting sun.

For the rest of the week, we`ll have some truly spectacular
weather, with mild temperatures and low humidity, especially
for mid-late July standards. The culprit will be a slow moving
pattern dominated by a western ridge and eastern trough. We`ll
be in the subsidence region to the west of the trough. This will
allow a surface high to setup shop over us for a few days. This
high will be coming from north central Canada, hence the
forecast with highs 5-10 degrees below normal with very
comfortable dewpoints (40s and 50s) for the rest of the week,
enjoy it!

For the weekend into next week, the change in the upper level
pattern is subtle, but enough to lead to some changes for us.
The western ridge will more or less remain in place, but the
eastern trough will depart the Great Lakes to the northeast.
This will move the subsidence region out of the upper MS Valley,
which will allow the surface high to start washing out. This
change will allow for a more southerly low level flow to
develop, which will allow highs to get back up into the 80s,
with dewpoints getting back into the 60s. Remove the upper
subsidence and its associated inversion and weak mid-level lapse
rates and you have an environment supportive of the return of
diurnal shower chances, which is more or less what the NBM
continues to show with it`s 20-40% PoPs that make their return
on Saturday.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1236 AM CDT Wed Jul 17 2024

Solid VFR conditions are expected throughout this TAF duration.
SCT mid-and-upper level clouds will drift southeastward around
a weak upper level circulation overnight, with skies mainly
clear by daybreak. Fair wx mid-level cumulus clouds are likely
to develop Wednesday afternoon, then dissipate Wednesday evening
allowing for clear skies Wednesday night. NW winds in the 5-10kt
range will prevail tonight through Wednesday afternoon then go
light/variable Wednesday night.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/
THU...VFR. Wind SW 5 kts.
FRI...VFR. Wind SW 5-10 kts.
SAT...VFR. Wind SW 5 kts.

&&

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

&&

$$

DISCUSSION...MPG
AVIATION...JPC