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000
FXUS63 KARX 302326
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
626 PM CDT MON MAY 30 2016

.SHORT TERM...(This evening through Tuesday)
Issued at 340 PM CDT Mon May 30 2016

Primary concerns through Tuesday include timing, coverage, and
strength of thunderstorms as a slow moving Pacific trough moves
across the Northern Plains and into the Upper MS River Valley.
30.20Z analysis shows the mid-upper level low across north-central
MT with a broad surface trough from northeast ND into western NE.
The warm front is well defined by developing cumulus this
afternoon and stretches across southwest MN into central IA. This
front will lift northward this evening and overnight, bringing a
chance for showers and storms for most of the forecast area.
Increasing moisture transport behind the front will allow elevated
instability to increase up to 1000 J/kg, but with weak overall
shear, not expecting any severe convection overnight.

Attention then turns to Tuesday as the low and surface cold front
march slowly eastward across MN. Trends in the 30.12Z models show
a much slower frontal progression, such that it doesn`t reach the
far western forecast area until near 00Z Wednesday. With the front
serving as the primary focus for additional thunderstorm
development, there could be a several hour break in convective
activity Tuesday morning into the early afternoon, especially
east of the MS River. By Tuesday afternoon however, MLCAPE
increases to between 1000 and 2000 J/kg. Deep layer shear is
rather weak, but there is upwards of 30 kts below 3 km. Because of
this, primary convective mode should be multi-cellular with some
strong to severe storms possible. Primary threats with the
strongest storms will be damaging wind, large hail, and heavy
downpours. For now, forecast area is highlighted by a marginal
risk, but wouldn`t be surprised if a small area is eventually
upgraded to a slight risk if higher instability/shear values can
be realized.

Will also want to watch for areas of heavy rain given PWATS
increasing to near 1.5 inches and upper level flow parallel to the
surface front. Not expecting flooding at this time with much of
the area still below normal precipitation for the month of May,
but heavy rain may result in rises on area rivers and some issues
in urban areas. All said, slowed the eastward progression of
higher POPs Tuesday afternoon and evening, exiting the easternmost
forecast area by 12Z Wednesday.

.LONG TERM...(Tuesday night through Monday)
Issued at 340 PM CDT Mon May 30 2016

Wednesday will be mostly dry, but could see some lingering showers
and isolated thunderstorms in post frontal air mass. It will be a
cooler and breezy day with highs in the 70s and westerly wind gusts
up to 25 mph. Thursday will be cool and dry with surface high
pressure dominating the regional weather pattern.

Synoptic pattern still on track for a major shift Friday into
early next week with an amplifying ridge across the intermountain
west, putting the eastern half of the CONUS in a broad trough
with northwest flow aloft across the forecast area. This increases
the chance for showers and thunderstorms with short-waves dropping
south from Canada. The strongest of these is forecast to move
through the area Friday night into Saturday, but chance POPs still
seem reasonable at this time. Higher confidence in temperatures
with daily highs generally in the 70s and lows in the 50s.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 626 PM CDT Mon May 30 2016

Scattered showers and thunderstorms will move across the TAF sites
tonight with more widespread showers and storms on Tuesday. Some
periods if MVFR to IFR conditions are possible in the steadier
rain. Otherwise, VFR conditions are expected.

&&

.ARX Watches/Warnings/Advisories...
WI...None.
MN...None.
IA...None.
&&

$$

SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...WETENKAMP





000
FXUS63 KARX 291159
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
659 AM CDT SUN MAY 29 2016

.SHORT TERM...(Today through Wednesday)
Issued at 320 AM CDT Sun May 29 2016

Showers speckle the radar scope out there early this morning, with
an upper trough overhead but lifting northeast while an associated
surface cold front is just about to slip out of the eastern CWA at
07Z. In addition to the smattering of showers, some fog and lower
stratus has developed in spots with a moist airmass in place and
lightening winds along/behind the front. Heading through day, the
primary forecast issue remains chances for any additional showers
this afternoon, and honestly have to say I`m not terribly impressed
by the potential. From a forcing perspective, there just isn`t a
whole lot once we lose our upper trough (and remaining showers) by
mid morning, though to be fair a weak shortwave crossing central
North and South Dakota currently is progged to slide over our way,
in addition to perhaps a weakish secondary surface trough axis
dropping into the area. The biggest issue looks to be boundary layer
moisture, with the NAM/GFS too high with dew point values well into
the mid 60s, while their respective mixed layer values and forecast
raobs suggest values down into the mid 50s look more reasonable. As
such, have a hard time seeing much if any instability development,
save for perhaps east of the Mississippi River where things may mix
out a little less to support maybe 250 J/KG MLCAPE beneath some
cooling aloft, maybe leading to a couple of showers.

Looking quiet tonight with low/mid level ridging firmly building in
aloft, with lower dew points and clear skies likely supporting
comfortable lows back into the 50s for most spots. With wet ground
from recent rains, could see some fog development, especially along
and east of the Mississippi in valley locations. Thereafter, some
trickiness into Memorial Day itself with regard to additional precip
chances. Guidance has really been struggling with northward extent
of returning moisture through Iowa the past few days, and gut
feeling is the more southerly displaced solutions with regard to
moisture/instability are the way to go as low level ridging hangs
firm across the area and low level flow maintains a northerly
component. That may change heading into Monday night with the
development of stronger return flow and approach of an elevated warm
front and lead wave in advance of a robust northern stream closed
low working toward the northern Plains. Broad layer warm advection
ascent should bring at least a risk for precip lifting north through
the area, though elevated instability remains meager with maybe 250-
500 J/KG CAPE and limited shear for no severe weather threat.

That northern Plains upper low is expected to shift into northern
Minnesota by Wednesday with broad ascent continuing to deliver some
additional rainfall across the area. Given expected widespread cloud
cover across the area through midweek, get the feeling that overall
instability will remain limited with the potential for curtailed
heating Tuesday afternoon, with probably only an isolated/scattered
thunder risk in a broader rain shield. Similar to Monday night, just
not seeing a whole lot of shear for any severe threat. Per current
trends, it appears rain will shut down quickly from west to east on
Wednesday as a cold front arrives and modest subsidence/drying sets
in through the day.

.LONG TERM...(Wednesday Night through Saturday)
Issued at 320 AM CDT Sun May 29 2016

In contrast to an active weather stretch for the start of the work
week, things are looking rather quiet into late week and next
weekend, with continued hints of notably cooler and less humid
conditions as upper troughing sits across the region while low level
ridging also dominates. With pronounced thermal troughing in place
and 850mb temps hovering in the 2-7C range, envision highs in the
mid 60s to mid 70s with some quite comfortable humidity levels.
Can`t completely rule out a diurnally driven shower on Thursday with
hints of a stronger shortwave dipping through the mean trough and
coolness aloft supporting some weak instability, with otherwise dry
conditions likely through Friday night, and maybe a few showers
returning by Saturday.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 655 AM CDT Sun May 29 2016

MVFR clouds rotating around a low over western Lake Superior will
affect the TAF sites through 29.17Z and then these clouds will
rise into the 4-5K foot range for the afternoon. Skies will then
clear tonight. A west and northwest wind will remain in the 10
to 15 knot range today and then become light and variable
tonight.

&&

.ARX Watches/Warnings/Advisories...
WI...None.
MN...None.
IA...None.
&&

$$

SHORT TERM...Lawrence
LONG TERM...Lawrence
AVIATION...BOYNE





000
FXUS63 KARX 290820
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
320 AM CDT SUN MAY 29 2016

.SHORT TERM...(Today through Wednesday)
Issued at 320 AM CDT Sun May 29 2016

Showers speckle the radar scope out there early this morning, with
an upper trough overhead but lifting northeast while an associated
surface cold front is just about to slip out of the eastern CWA at
07Z. In addition to the smattering of showers, some fog and lower
stratus has developed in spots with a moist airmass in place and
lightening winds along/behind the front. Heading through day, the
primary forecast issue remains chances for any additional showers
this afternoon, and honestly have to say I`m not terribly impressed
by the potential. From a forcing perspective, there just isn`t a
whole lot once we lose our upper trough (and remaining showers) by
mid morning, though to be fair a weak shortwave crossing central
North and South Dakota currently is progged to slide over our way,
in addition to perhaps a weakish secondary surface trough axis
dropping into the area. The biggest issue looks to be boundary layer
moisture, with the NAM/GFS too high with dew point values well into
the mid 60s, while their respective mixed layer values and forecast
raobs suggest values down into the mid 50s look more reasonable. As
such, have a hard time seeing much if any instability development,
save for perhaps east of the Mississippi River where things may mix
out a little less to support maybe 250 J/KG MLCAPE beneath some
cooling aloft, maybe leading to a couple of showers.

Looking quiet tonight with low/mid level ridging firmly building in
aloft, with lower dew points and clear skies likely supporting
comfortable lows back into the 50s for most spots. With wet ground
from recent rains, could see some fog development, especially along
and east of the Mississippi in valley locations. Thereafter, some
trickiness into Memorial Day itself with regard to additional precip
chances. Guidance has really been struggling with northward extent
of returning moisture through Iowa the past few days, and gut
feeling is the more southerly displaced solutions with regard to
moisture/instability are the way to go as low level ridging hangs
firm across the area and low level flow maintains a northerly
component. That may change heading into Monday night with the
development of stronger return flow and approach of an elevated warm
front and lead wave in advance of a robust northern stream closed
low working toward the northern Plains. Broad layer warm advection
ascent should bring at least a risk for precip lifting north through
the area, though elevated instability remains meager with maybe 250-
500 J/KG CAPE and limited shear for no severe weather threat.

That northern Plains upper low is expected to shift into northern
Minnesota by Wednesday with broad ascent continuing to deliver some
additional rainfall across the area. Given expected widespread cloud
cover across the area through midweek, get the feeling that overall
instability will remain limited with the potential for curtailed
heating Tuesday afternoon, with probably only an isolated/scattered
thunder risk in a broader rain shield. Similar to Monday night, just
not seeing a whole lot of shear for any severe threat. Per current
trends, it appears rain will shut down quickly from west to east on
Wednesday as a cold front arrives and modest subsidence/drying sets
in through the day.

.LONG TERM...(Wednesday Night through Saturday)
Issued at 320 AM CDT Sun May 29 2016

In contrast to an active weather stretch for the start of the work
week, things are looking rather quiet into late week and next
weekend, with continued hints of notably cooler and less humid
conditions as upper troughing sits across the region while low level
ridging also dominates. With pronounced thermal troughing in place
and 850mb temps hovering in the 2-7C range, envision highs in the
mid 60s to mid 70s with some quite comfortable humidity levels.
Can`t completely rule out a diurnally driven shower on Thursday with
hints of a stronger shortwave dipping through the mean trough and
coolness aloft supporting some weak instability, with otherwise dry
conditions likely through Friday night, and maybe a few showers
returning by Saturday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1150 PM CDT Sat May 28 2016

Periods of MVFR to IFR conditions are expected at the TAF sites
tonight in low stratus and BR. Low pressure moves across the TAF
sites tonight, and combined with a moist airmass, will produce
some stratus and BR at times. KLSE will mainly see the MVFR
conditions while KRST is expected to see IFR. Mixing increases
Sunday morning and conditions will improve to VFR. Look for west
winds to increase into the 12 to 14 kt range during the day on
Sunday with gusts to 22 kts possible. Also, a broken stratocumulus
deck is expected on Sunday with cloud bases in the 3500 to 4000 ft
range. Clouds will scattered out Sunday evening and west winds
subside as weak high pressure edges in.

&&

.ARX Watches/Warnings/Advisories...
WI...None.
MN...None.
IA...None.
&&

$$

SHORT TERM...Lawrence
LONG TERM...Lawrence
AVIATION...WETENKAMP





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