309 
FXUS63 KMPX 170913
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
413 AM CDT Fri May 17 2019

.SHORT TERM...(Today through Saturday)
Issued at 415 AM CDT Fri May 17 2019

A stationary front roughly along I-80 this morning will begin 
lifting back north as a warm front today and tonight. Showers and 
thunderstorms north of the boundary have been prevalent across 
northern and central Iowa into southeastern South Dakota and 
southwestern Minnesota overnight. Dry northeasterly flow across the 
rest of Minnesota and Wisconsin are keeping the showers at bay for 
now, but as the mid level ridge begins to build over the Mississippi 
Valley later today, southerly flow in the mid levels will strengthen 
and deeper moisture will be transported into the Upper Midwest. This 
will allow the showers and storms to gradually build northward today 
and especially tonight on the nose of a 50 kt LLJ encompassing much 
of the Plains. This forcing and strong moisture transport will 
foster widespread thunderstorms tonight.
Steepening mid level lapse rates late and effective wind shear of 40 
kts should get some storms to produce large hail across southern and 
western MN. Otherwise, heavy rainfall is possible but it doesn't 
appear at this time we'll have excessive amounts with training of 
intense cores unlikely. 

The surface warm front now appears will lift into southern Minnesota 
Saturday. There will be an intense temperature gradient somewhere 
near the Minnesota River, where highs in the 70s and 80s are 
expected south and only 40s to low 50s to the north. Surface-based 
instability should develop in the warm sector by midday and could 
allow for severe storms to continue before the surface low passes to 
the east. A few elevated storms capable of large hail are possible 
anywhere in the CWA, however, with sufficient instability above a 
very strong moist inversion around 850 mb.

.LONG TERM...(Saturday night through Thursday)
Issued at 400 AM CDT Fri May 17 2019

Model trends continue to lift the upper low across the region
Saturday into Sunday. This will generate showers and thunderstorms
across the region. Heavy rain will be possible, especially across
the eastn half of the CWA/east of I-35 into western WI/ as the 
best forcing and moisture lift northeast. With the clouds and
rain, temerpatures will struggle to warm through the 40s for
highs. Some 25 degrees below normal for much of the area. 

As the system lifts out Sunday night, clearing will take place to
the west. This will need to be monitored for possible frost 
potential, especailly if clearing is faster. Some sunhine is 
expected for Monday with high pressure dominating the region. 
Temperatures are expected to mderate some, but remain about 10 
degrees below normal. 

Models continue the unsettled pattern through the remainder of 
the period. Another upper trough lifts northeast across the
southwest into the Plains affecting the region Tuesday into
Wednesday with another round of thunder. This has the potential 
of generating another heavy rain event with precipitable water
values forecast over an inch. This pattern repeats again later 
Thursday into next Friday. Temperatures may moderate some, perhaps
close to normal by Friday. 

Area rivers and streams will likely be on the rise again after 
this extended period of rain. 

&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1132 PM CDT Thu May 16 2019

Continued trend from 00z TAFs of delaying precip mention and MVFR
cig arrival due to very dry east low level flow we will have
Friday. Expect scattered showers to expand north during the 
afternoon as muCAPE gradient currently across IA lifts into 
central MN. More concentrated area of thunderstorms is expected to
come out of southeast SD Friday evening, working across southern 
MN late Friday night. Again stayed close to an HREF/SREF mvfr cig 
probability for timing MVFR cigs in across southern MN.

KMSP...Expect a couple of bursts of precip this period. First 
will come around 00z as elevated CAPE gradient lifts through, with
another concentrated area arriving around 10z, which will likely 
be a line of stronger storms.

/OUTLOOK FOR KMSP/
SAT...MVFR/IFR. -SHRA/TSRA likely. Wind ENE 10G20 kts.
SUN...IFR/MVFR. -SHRA. Wind NE 15G25 kts.
Mon...VFR. Wind NE 5 kts.

&&

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

$$

SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...MPG