Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 200430

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1130 PM CDT THU MAY 19 2016

.SHORT TERM...(This evening through Friday)
Issued at 346 PM CDT Thu May 19 2016

A few light showers have developed across western Minnesota this
afternoon, but the boundary layer is so dry that sprinkles at
best result. Any sprinkle threat will be short-lived late this
afternoon and a stabilizing of the boundary layer should allow
diurnal cu to dissipate some this evening.

A similar situation will develop Friday with a return of diurnal
cu, this time perhaps broken or overcast. Despite a fair amount
of QPF on the NAM, GFS, and various hi-res models, the instability
and cloud layers are very shallow, and the boundary layer is dry.
Therefore, another round of isolated sprinkles appear likely. Kept
pops below 15 percent and kept all precip amounts zero.

.LONG TERM...(Friday night through Thursday)
Issued at 346 PM CDT Thu May 19 2016

Only major change in the extended period is to slow down the arrival
of the precipitation late in the weekend, especially across eastern
Minnesota and western Wisconsin.

Models have been fairly consistent on the evolution of the mean
trough across the western part of North America, slowly moving east-
northeast across the northern Rockies, and into the southern plains
of Canadian by early next week. Both the GFS ensembles, and the 50h
means of the EC/GEM support a slower movement as the upper ridge
holds across the Great Lakes region, washing out/weakening the upper
trough over the Rockies as it moves northeast.

One weather element that seems to be holding steady, is the
persistent warming and increasing moisture by late in the weekend
and into next week. This will eventually lead to higher chances of
thunderstorms starting early next week. As with the 50h mean heights
holding across the Great Lakes, 85h mean heights are similar leading
to southwest flow aloft, and possibly holding the surface boundary
in the Upper Midwest through next week. Timing and how widespread
the activity becomes remains problematic due to subtle deviations in
the boundary layer. One of the weather elements that has been very
persistent is the increasing PWAT values by Monday. These values
increase to above 1.50" which is in the 95 percentile for normal
values in late May. Have added heavy rainfall to the forecast on
Monday due to this parameter. As for severe weather chances, there
remains adequate moisture, but timing and instability remains
questionable as the front nears the area late Sunday night, and into

Beyond Monday, as with the persistent southwest flow and another
strong short wave moving through this flow regime, chances of
precipitation will continue.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1128 PM CDT Thu May 19 2016

Few clouds overnight with light southeasterly winds.  Tomorrow
will be similar to today with a diurnally driven cumulus field
expected to pop during the day. Overall, VFR conditions with no
weather issues expected.

KMSP...VFR throughout with no weather issues.

SAT...VFR. Wind SE 5-10 kts.
SUN...VFR. Wind S 10-20 kts.
MON...VFR. Chc -TSRA. Wind SW 15-20 kts.


.MPX Watches/Warnings/Advisories...


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