Area Forecast Discussion
Issued by NWS Twin Cities, MN
FXUS63 KMPX 210350 AAB
Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
1050 PM CDT FRI MAY 20 2016
.SHORT TERM...(This evening through Saturday)
Issued at 243 PM CDT Fri May 20 2016
Very little change in the forecast for the next 24-36 hours as
weak high pressure begins to build across the western Great
Lakes. The consistently moist bias /models/ in the boundary layer
will likely continue through Saturday. This basically means little
in the way of cloud cover and very dry boundary layer moisture.
Mixing heights will likely rise above 5-6k which has been the
trend over the past day or so. Although cloud cover today,
especially in western Minnesota has been higher than expected,
tomorrow will see much more sunshine with temperatures rising into
the mid to upper 70s. A few 80s are not out of the question in
western Minnesota along with light south winds.
.LONG TERM...(Saturday night through Friday)
Issued at 243 PM CDT Fri May 20 2016
Saturday Night and Sunday...This 24-hour period will be the most
quiet period throughout the extended portion of the forecast. An
upper level 500mb ridge will align itself atop the western
Minnesota border while extensive high pressure centered over New
England will still have its western extent over the Upper
Mississippi River region. Both features still steadily shift
eastward Saturday night into Sunday, allowing for a deep southerly
flow on the backside of the high and the western side of the sharp
ridge axis. Aside from an increase in cloud cover mid-to-late day
on Sunday, the area looks to be free from precipitation while
temperatures continue their increase. Highs will hit the upper 70s
to lower 80s Sunday afternoon.
Sunday Night through Tuesday...The aforementioned upper level
ridge axis will shift eastward into the Great Lakes and western
Ohio River valley regions Sunday night. At the same time, a deep
upper level low over the Pacific Northwest will slowly move east
northeast into south-central Canada over the weekend. This low
will stall out over southern Saskatchewan province early next
week, creating a persistent WSW to ENE flow aloft. At the surface,
a slow-moving cold front over the Rockies will shift into the
Plains states, on its way to the border between the Dakotas and
Minnesota by daybreak Monday morning. The surge of moisture from
the Gulf of Mexico in advance of this front will allow for showers
and thunderstorms to develop late Sunday night in western
Minnesota with the precipitation steadily moving eastward Monday.
Much of the coverage area can expect period of showers and
thunderstorms Monday into Monday night, then gradually lessening
in coverage through Tuesday. Due to a high moisture surge to the
tune of nearly 1.50 inch precipitable water, some of the storms
may contain localized moderate to heavy rain. As for severe
weather potential, MUCAPE is still not all that impressive,
generally in the 500-1000 J/KG range. However, should some of the
more impressive shortwaves ride northeast through the progressive
flow, some stronger storms cannot be ruled out for during the day
on Monday. That said, the better chances for severe weather will
be south of the WFO MPX coverage area. Temperatures will continue
to run mild due to the lack of airmass change over the area
despite the presence of the surface fronts. Highs will remain in
the middle to upper 70s with lows in the middle 50s to lower 60s.
Wednesday through Friday...A fairly progressive pattern will
remain in place aloft over the region as an upper level low stalls
out over the southwestern states and the Bermuda high develops off
the East Coast. Several shortwave disturbances will glide through
the region while the surface front stalls out over the Central
Plains through the Ohio Valley, just south of MN and WI. Though
this setup will likely mitigate any strong/severe storms,
scattered showers and thunderstorms will remain in the forecast
during the middle to latter portions of the week as the strong
low-to-mid level surge of moisture will continue with the surface
front nearby. Mild temperatures will continue, though slightly
cooler than the start of the week. Highs will drop to between the
upper 60s to middle 70s with lows generally in the 50s.
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1050 PM CDT Fri May 20 2016
VFR conditions are expected for at least the next 48 hours. Mainly
clear skies expected overnight and Sunday. Light and variable
KMSP...No additional concerns.
/OUTLOOK FOR KMSP/
SUN...VFR. Wind S 10-15 kts.
MON...Mainly VFR. TSRA likely with MVFR possible. Wind S 10-15 kts.
TUE...Mainly VFR. Chc TSRA/MVFR. Wind S 5 kts.