Area Forecast Discussion
Issued by NWS Twin Cities, MN

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314
FXUS63 KMPX 171749
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1249 PM CDT Fri May 17 2024

.KEY MESSAGES...

- Low RH values Saturday afternoon could result in areas of
  elevated fire weather conditions.

- Increasing confidence for showers and thunderstorms Sunday
  night into Monday morning. The risk for severe weather is
  low.

- An active pattern set to begin Sunday night. Multiple chances
  for rain, possibly heavy, and thunderstorms over the next
  seven days.

&&

.DISCUSSION...
Issued at 322 AM CDT Fri May 17 2024

TODAY THROUGH SUNDAY... Scattered thunderstorms across west &
central Minnesota north of I-94 this morning that`ll taper off
as the storms move further east into a more stable and drier
environment. Warm air advection will kick in today as an
impressive low level jet roaring aloft. Temperatures climb into
the low to mid 80s across MN & WI, with a solid shot at 90
across western Minnesota. There is a non-zero chance for
isolated thunderstorms this afternoon, but there is a lot
working against it. Forecast soundings highlight an impressive
inverted V featuring very dry low levels that`ll limit any
chance for precip to make it to the surface (virga). Saturday
will feature another pleasantly warm day, but we`ll have to keep
an eye on elevated fire weather potential Saturday afternoon
post-fropa as RH values could drop into the 20-25 percent range.


A sfc cold front will pass through the Upper Midwest. This will
present western Wisconsin with a slight chance for thunderstorms to
develop along it Saturday afternoon. Rusk Co is included in SPC`s
day 2 outlook, but most CAMs don`t initiate until past the MPX WI
CWA. Sunday will see an uptick in PoPs throughout the day as
southeast flow will ramp up moisture advection into the region. The
quasi-stationary front across Iowa will become a focal point for a
rather active pattern setting up over the next week or so.

SUNDAY NIGHT THROUGH THURSDAY NIGHT... A mid-level trough amplifying
over the western CONUS will drive southwest flow aloft over the
region throughout the week. WPC has highlighted days 3-5 with
marginal chances for excessive rainfall. The first shortwave moves
through Sunday night and will bring widespread rain and
thunderstorms across Minnesota and western Wisconsin. It looks like
the best chance for widespread and heavy rain will be across S MN
and into W WI. Monday will dry out, but by Monday night another
round of storms and showers will ride along the stationary boundary
set up across the Upper Mississippi Valley. This batch of possible
heavy rainfall will be in the late Monday into Tuesday time frame
when guidance indicates a more potent shortwave energy lifting
across the stationary frontal boundary draped across the region.
Model uncertainty spikes later into the week but it certainly looks
possible that additional round of showers Wednesday evening into
Thursday morning.

Showers could linger into Thursday before drying out on Friday.
Temperatures start off in the extended with highs in the upper
70s Sunday and Monday. However, temperatures will trend cooler
in the wake of the Tuesday low pressure system/frontal boundary
pushing off to our south and east. This pattern also would
suggest a cloudier forecast that would support cooler
temperatures. This active pattern looks to continue into
Memorial Day weekend before things "dry out" toward the end of
May.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1226 PM CDT Fri May 17 2024

Morning line of showers has all but dissipated in western
Wisconsin, with satellite revealing mostly clear skies over the
Minnesota terminals. Southerly winds will increase this
afternoon as a warm front lifts through the state. Have
added/continued the potential for LLWS this evening given the
expected strengthening LLJ across the Upper Midwest. EAU is the
only site to not feature wind shear concerns at this time,
given the the expected weakening of the LLJ with eastern extent
tomorrow morning. Also of note, latest CAM guidance has trended
upward with the potential for isolated convection on the nose
of the LLJ this afternoon and evening. AXN, STC, MSP, and RNH
would be the primary terminals to watch for this activity,
however the chances appear too low/isolated to include in the
18z TAF set.

KMSP...Eastward approach of the strengthening LLJ has prompted
the threat for LLWS overnight, so have opted to include mention
in the 18z TAF. Threat for LLWS will decrease by daybreak
Saturday, followed by a shift in the winds from southerly to
westerly by midday.

/OUTLOOK FOR KMSP/
SUN...VFR. MVFR/SHRA likely late. Wind SE 10-15kts.
MON...MVFR/-TSRA thru mrng. VFR chc SHRA aftn. Wind SE 5-10kts.
TUE..MVFR/-TSRA likely. Wind NE 10-15 kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...Strus