Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 272030

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

.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 18Z TAFS through 18Z Saturday afternoon)
Issued at 1217 PM CDT Fri May 27 2016

MVFR and some IFR will predominate through he period as the
surface trough lingers over the area and a few weak shortwaves
move through. Main windows for poor conditions look to be this
afternoon, with some improvement from late afternoon into this
evening, then again late tonight and Saturday morning. Stuck
fairly close to timing of LAMP guidance, but in general did not go
quite as pessimistic with the specifics. Thunder is a possibility,
but doesn`t look sufficiently likely to include at this point,
especially with the better chances for that looking like they`d
occur with the precipitation late tonight/Saturday morning.

KMSP...Have reasonable confidence in the overall forecast and
timing, but do believe it`s possible that conditions could be a
bit worse with both ceiling and visibility in the 09Z-15Z time
period, so subsequent forecasts may need to adjust.

Saturday night...MVFR ceilings possible. Northwest wind 5 to 10
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...


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