Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 291948

Area Forecast Discussion
National Weather Service La Crosse WI
248 PM CDT SUN MAY 29 2016

.SHORT TERM...(This evening through Monday)
Issued at 248 PM CDT Sun May 29 2016

Most immediate concern is convective chances this afternoon as an
area of MLCAPE from 1000 to 1500 J/kg interacts with an approaching
short-wave aloft. Already seeing a few isolated thunderstorms pop
up near the MN/IA border region and expect additional scattered
thunderstorms through sunset mainly along and south of the I-90
corridor. The strongest storms may be capable of producing gusty
winds up to 40 mph and small hail. For tonight, expect dry
conditions and clearing skies with temperatures dropping into the
50s. Could see some patchy fog mainly along and east of the
MS River.

Memorial Day is shaping up to be quite nice. With short-wave
ridging aloft and high pressure at the surface, expect partly
sunny skies and temperatures in the upper 70s to lower 80s. Light
westerly winds early in the day will slowly shift to the south.
Dew point temperatures will also be in the 50s, making for a less
muggy day. While there is a slight chance for showers and storms
across portions of northeast IA late in the afternoon, the vast
majority of convective activity will stay well west of the
forecast area, coincident with the best moisture transport and
instability axis across the Dakotas into the central Plains.

.LONG TERM...(Monday night through Sunday)
Issued at 248 PM CDT Sun May 29 2016

A Pacific trough ejects eastward from the northern Rockies into
the western Dakotas Monday night, lifting a warm front across the
forecast area. While deep-layer shear is weak, increasing moisture
transport along a 25 to 35 kt 850 hPa nocturnal jet combined with
some lingering mid-level instability could result in some scattered
showers and storms. Much better chance for more widespread showers
and storms will occur on Tuesday as weakening surface cold front
sweeps across the forecast area. Stronger mid-upper level flow
lags well behind the front, but with 20 to 30 kts of 0-3 km shear
and 1000 to 1500 J/kg of MLCAPE, could see a few stronger storms
during the day. This agrees well with current marginal risk from
the SPC Day 3 outlook.

Lingering showers and storms move east and out of the region on
Wednesday with drier, breezy conditions in the front`s wake. After
dry and cooler conditions Thursday/Friday, precip chances return
Friday night into the weekend as ill-resolved short-waves drop
south in northwest flow aloft with ridging building across the
intermountain west. Temperatures will be noticeably cooler
compared to recent days, but still near normal for early June with
highs generally in the mid to upper 70s.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1242 PM CDT Sun May 29 2016

Isolated showers developing this last hour near the KRST/KLSE TAF
sites. AS such...added VCSH through the rest of this afternoon.
Latest forecast model data shows the atmosphere destabilizing
more this may have to eventually include VCTS or
TSRA in TAFs as well. Will maintain a close eye on this as the
afternoon progresses. Otherwise...expecting MVFR cumulus. West
winds will be a bit gusty as well in the 10-15 mph...gusting 20-25
mph. Look for these winds to rapidly die off this evening along
with skies becoming mostly clear after sunset. A few altocumulus
clouds may then drift into the region by mid Memorial Day morning
ahead of a warm front over the Plains.


.ARX Watches/Warnings/Advisories...


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