Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 201128 AAA

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
628 AM CDT Mon May 20 2019

.SHORT TERM...(Today through Tuesday)
Issued at 404 AM CDT Mon May 20 2019

Temperatures have fallen into the mid 30s across much of the area
early this morning following the rapid dissipation of the clouds.
Any frost will be quick to burn off as the sun rises.

It will be a mainly sunny day, and a bit warmer from the past
couple days, but still much below normal in the upper 50s to low
60s. Some high clouds will increase late in the day and especially

The system responsible for the tornado outbreak in the southern
Plains today will lift northeast to eastern Nebraska by Tuesday
evening as a sub 990 mb low. The pressure gradient will tighten
Tuesday and low level easterly flow will increase significantly by
afternoon. Forecast soundings show winds as high as 50 kts within
the mixed layer. As rain lifts north and encompasses the entire
area late in the day, the profile may no longer be dry adiabatic,
which should limit the potential of 50 kt (~60 mph) gusts.
However, there should be enough wind mixing down to get 40 to 50
mph gusts. Increased winds quite a bit from previous forecasts and
we may need a Wind Advisory in coming forecasts.

.LONG TERM...(Tuesday night through Sunday)
Issued at 404 AM CDT Mon May 20 2019

The longer term upper level flow pattern continues the western
CONUS trough and ridging to the east favoring the unsettled
pattern across the region through the week. There continue to be
some indications of some warming by midweek and continuing into
next weekend. Temperatures trend toward normal with the warmest
day centered around Friday.

The wester trough lifts a strong upper trough over the region
Tuesday night and into Wednesday. Strongest forcing lifts Tuesday
night with remaining occluded front lifting over the area
Wednesday, Some warming indicated on models with instability
increase during the day as the boundary exits the area. May see
some isolated thunder with this.

We see a dry day for the most part Thursday as the western trough
reloads and lifts another wave over the region Thursday night
into Friday. This looks to have the better thunder potential. GFS
indicating MUCAPES around 1500 J/KG Friday with mid level lapse
rates around 7 C/KM and best LI`s around minus 6. Could see strong
storms depending on timing with frontal system.

Following this system, the deterministic models diverge some in
handling the upcoming weekend. Saturday appears to be the driest
of the weekend, with the GFS trying to merge northern and southern
stream trough energy across the northern states later Sunday and
Monday. The ECMWF is less so and lifts a front north with
overrunning rain/thunder developing Monday. It remains to be seen
what actually occurs and will continue to monitor overall trends
into the week. Temperatures trend cooler again into the weekend
perhaps 5 to 10 degrees below normal.


.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 628 AM CDT Mon May 20 2019

VFR conditions are expected through the period.

KMSP...No additional concerns.

Tue...VFR. MVFR and IFR/SHRA likely late. Wind E at 25G40 kts.
Wed...MVFR/IFR/-SHRA early, then VFR. Wind SE at 10-15G25 kts
becoming SW 15G30kts.
Thu...MVFR possible. Chc -SHRA. Wind light/variable.


WI...Frost Advisory until 8 AM CDT this morning for WIZ014-023-024.

MN...Frost Advisory until 8 AM CDT this morning for MNZ041>045-



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