Area Forecast Discussion
Issued by NWS Twin Cities, MN

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790
FXUS63 KMPX 300604
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
104 AM CDT Tue Apr 30 2024

.KEY MESSAGES...

- Slight Risk (level 2 of 5) of severe weather for south central
  Minnesota Tuesday afternoon for the next round of showers &
  thunderstorms. The main threats are damaging wind and large
  hail, and an isolated tornado or two can`t be ruled out.

- Pattern to remain active with rain chances every 24 to 48
  hours, with another widespread soaking rain looking likely
  Thursday and more showers possible Saturday and again early
  next week.

&&

.DISCUSSION...
Issued at 324 PM CDT Mon Apr 29 2024

It`s yet another soggy Spring day across the Upper Midwest. The sfc
low is pivoting over top of E MN this afternoon accompanied by
scattered showers impacting portions of central and eastern
Minnesota. Elsewhere, mist & drizzle persist with light winds
present. Showers & drizzle will gradually taper off through the
afternoon. Temperatures will stagnant where they`ve been all day, in
the upper 40s, due to the weak low level flow & expansive stratus
deck overhead. As I alluded to yesterday, this is a perfectly fine
mid-March day we`re observing in late April. Jokes aside, we`ll see
the low level stratus scatter out by Tuesday sunrise across MN and
late morning for west central WI. This will cause areas in W & C MN
to cool into the mid to upper 30s tonight and there could be patchy
frost in these areas. Elsewhere we`ll "cool" into the lower 40s.
We`ll have a brief reprieve between weather systems tonight thru
Tuesday morning.

Our attention turns to Tuesday, specifically Tuesday afternoon, as a
warm front will open the door for our next round of showers &
thunderstorms. An impressive shortwave will dig into the north
central CONUS Tuesday. This will push through a thermal ridge during
the day with temperatures warming into the upper 60s and lower 70s.
With that surge of WAA comes moisture & the threat of severe
weather. Forecast soundings across south central Minnesota show
between 500 to 1000 J/Kg CAPE with a very favorable shear environment
conducive to organized severe weather. A closer look at the wind
profiles show long, curved hodographs that should do the heavy
lifting under the weaker thermal environment. A low CAPE/high shear
set up along and infront of the cold front can produce all severe
hazards, despite the limitations of instability & lapse rates should
keep constraints on the event. Storms look to develop Tuesday
afternoon in the eastern Dakotas before tracking into SW and W MN.
The updated day two maintained the slight risk across portions of
south-central MN and a marginal risk through the Twin Cities and
west central WI. Updraft helicity tracks suggest we`ll see storms
weaken as they move west to east with a declining severe threat.
Outside of the severe threat, guidance trends maintain that we`ll
see another good soaking rain. QPF forecasts are between 0.5 to
0.75" across much of the area with the potential for locally higher
amounts in areas with training convection in SC MN.

Temperatures remain seasonal beyond Tuesday with highs in the 60s
through the weekend. There isn`t any big warm up on the way... at
least for now. The pattern will drive another system through
Thursday and we`ll remain on the cold side so severe concerns will
remain to our south. This will bring another opportunity for
widespread rain with a half inch to an inch seeming more and more
plausible as close in. Friday will dry out and see the return of our
old friend gusty wind. It`ll be below advisory criteria so it`ll be
nothing more than a nuisance for those out and about. The weekend
will offer yet another chance for rain on Saturday as a wave ejects
from the western CONUS BUT the spread in guidance is too significant
for anything more than chance PoPs.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1243 AM CDT Tue Apr 30 2024

GOES satellite reveals the back edge of the stratus gradually
clearing from southwest to northeast. RWF, MKT, MSP, STC, and
RNH have all improved to VFR early this morning, with MVFR
ceilings prevailing at the 06z TAF issuance at AXN and EAU.
Patchy areas of fog may develop shortly before/just after
daybreak at the northernmost terminals, before daytime winds
begin to increase. Hi-res guidance remains in excellent
agreement with the arrival time of a line of rain and
thunderstorms this afternoon and evening. Have included -TSRA at
RWF, MKT, and MSP. While rain is likely at the other TAF sites,
the chance of thunder appears lower. Winds will shift and
increase out of the west behind the line of convection.

KMSP...VFR through the overnight with the outside chance of some
patchy fog developing towards daybreak. Potential was too low to
include in the TAF. Opted to convert the PROB30 into a
prevailing line of -TSRA starting at 22z given the strong
agreement in forecast guidance. Winds kick out of the west by
3/4z.

/OUTLOOK FOR KMSP/
WED...VFR. Wind W 5-15 kts.
THU...MVFR/-RA likely. Wind E 10-15G25 kts.
FRI...VFR. Wind W 10-15G25kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...Strus