Area Forecast Discussion
Issued by NWS Twin Cities, MN

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534
FXUS63 KMPX 280439
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1139 PM CDT FRI MAY 27 2016

.UPDATE...for 06z aviation discussion below

&&

.SHORT TERM...(This evening through Saturday)
Issued at 325 PM CDT Fri May 27 2016

Things look to remain unsettled through the short term period as the
surface boundary continues to linger across the region. Current slug
of precipitation should shift north of most of the area this evening
as the shortwave helping to drive it pushes north. The next feature
of interest can be seen over the central Plains in water vapor
imagery, rotating around the main upper low. This looks to help
drive another area of showers with perhaps a few embedded
thunderstorms north into the area late tonight into Saturday
morning. We`ll eventually see the primary surface low work toward
the area by Saturday evening. Certainly cannot go with any
completely dry time frame through the period given lingering
elevated instability and continued southerly flow of moisture, but
this evening into the overnight appears to be the best time frame
for that possibility. The CAM guidance is in decent agreement on
this idea as well, and doesn`t really bring a more consolidated area
of precipitation back into the area until Saturday morning, with
that then continuing for much of the day, which makes sense given
the timing of the upper level wave and approaching surface low.
Temperatures could be tricky on Saturday if we are able to see any
decent breaks in cloud cover, since readings could quickly surge
above forecast values for a short time.

.LONG TERM...(Saturday night through Friday)
Issued at 325 PM CDT Fri May 27 2016

Confidence remains low on timing and how widespread the
thunderstorm activity remains for Saturday night, through Monday.
However, there remains enough consistency to lower chances once
the surface low moves out of the area late Saturday night, with a
broad area of drier westerlies behind this system on Sunday,
Sunday night. It still looks relativity good for outdoor
activities on Sunday and most of Monday.

By Monday evening, a strong storm system that will be moving
onshore in the Pacific Northwest this weekend, will begin to
spread deeper moisture northward across the Plains, and into the
Upper Midwest by Monday. However, initial dry air mass, and some
timing problems associated with the system moving onshore this
weekend, will lead to some uncertainties of timing for the next
batch of widespread rainfall. Although confidence is high for
another widespread rainfall event early next week, have kept
chances from 45 to 65% Monday night through Tuesday night. The
amount of jet energy and moisture with this system should lead to
another widespread 1-2" rainfall event by Wednesday morning.

The upper air pattern will begin to change from south-southwest,
to a more northwest-north flow by late next week. Depending upon
the strength of a deepening trough developing late next week, will
depend upon how cool temperature will play out. As with a pattern
change of this significances, deep moisture and instability
parameters will lower, so severe weather chances will diminish.

The latest probabilistic forecast of the GEFS /Ensemble of the
GFS/ for the 6-14 day period does show an anomalous upper trough
deepening across the eastern United States. This type of pattern
is also conducive for much drier conditions for early June.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1140 PM CDT Fri May 27 2016

The next batch of more concentrated showers will lift north into
the area from the south overnight, and affect the TAF sites
between 09z and 17z. There will likely be some isolated thunder,
but probability/coverage at any one site is too low for inclusion
in the TAF. Once the precip starts, expect it to be pretty dreary
until we see breaks in the precip /and possibly even scattering
clouds/ during the afternoon. IFR/MVFR conditions will prevail
through Saturday morning. Those breaks could fuel afternoon
thunderstorm development however...especially closer to the
surface low over southwest MN near KRWF. Light north/northeast to
variable winds will become south/southwest Saturday.

KMSP...
Expect MVFR conditions with sub-1700ft cigs to prevail through
Saturday morning. Area of showers looks to arrive around/after
11z Sat. We do have a chance to scour out the MVFR deck on
Saturday afternoon, but confidence is low. Could also see
thunderstorm development Saturday afternoon/eve.

/OUTLOOK FOR KMSP/
Sunday...VFR, but brief MVFR possible with a chance of showers and
thunderstorms. West wind 5 to 15 knots.
Sunday night and Monday...VFR. Variable wind less than 10 knots.
Monday night and Tuesday...MVFR ceilings and visibilities expected
with a chance of showers and thunderstorms. Southeast wind 10 to
15 knots.

&&

.MPX Watches/Warnings/Advisories...
WI...None.
MN...None.
&&

$$

SHORT TERM...
LONG TERM...JLT
AVIATION...LS



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