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Area forecast discussion 
National Weather Service La Crosse WI
1208 am CDT Friday may 29 2015

issued at 954 PM CDT Thursday may 28 2015

The models are still showing that the 850 mb moisture will
increase overnight as a short wave trough moves northeast through
the area. However am a bit concerned that recent radar trends are
on a diminishing trend and the rap has the moisture transport
more into southwest and central will have to watch
this trend closely overnight. With a bit more
uncertainty...lowered the shower chances a bit overnight.

On Friday morning...many of mesoscale models are showing that the area
will see subsidence in the wake of the overnight short wave. As a
result...they have trended drier. Due to this lower...the
precipitation chances during this time frame.


Short term...(tonight through Friday night)
issued at 318 PM CDT Thursday may 28 2015

Water vapor imagery/data analysis has a middle-level shortwave ridge
in place over the upper Mississippi River valley while a shortwave
trough was headed toward the area from the Central Plains.
Meanwhile...warm air advection ahead of a weaker wave pushing across
southern Canada was producing widely scattered showers/isolated
thunderstorms across northern WI. Otherwise...general warm air
advection across the area has pushed temperatures into the upper 70s
to the lower 80s.

Will be watching the shortwave trough ejecting northeast out of the
Central Plains and through the upper Mississippi River valley. Radar
mosaic showing fairly widespread showers and thunderstorms
associated with this wave across eastern NE/Kansas and southwest Iowa into
northern MO. Look for showers/thunderstorms to push into northeast
Iowa by early this evening...spread northeast across most of the area
after midnight...then tapering off from southwest to northeast
through Friday morning. With this trend...thinking there will be
somewhat of a break in the action during the late morning/early
afternoon for some heating in advance of a cold front moving through
late afternoon/evening hours. NAM BUFKIT showing moderate amount of
cape per BUFKIT in the 1500-2500j/kg...mainly east of the
Mississippi River. However...0-3km bulk shear is rather limited for
widespread organized severe event. Main severe threat would be some
small hail/sporadic damaging wind gusts along with heavy rain due to
higher precipitable water values in the 1.5-1.7 inch range.

Long term...(saturday through thursday)
issued at 318 PM CDT Thursday may 28 2015

After some morning shower/thunderstorm chances in the vicinity of
departing cold front across northeast Iowa into southern WI...look for
cooler drier air to overtake the area as Canadian high pressure
pushes in. Highs are only expected to top off in the 60s.

Will have to watch frost potential Saturday night/early Sunday
morning as high camps out overhead. Most susceptible area would be
the central sand country of WI/northeast of I-94.

Looks like a fairly long respite from the damp weather of late.
Sunday through Wednesday look dry as a ridge f high pressure holds
across the region. Also...look for a slow warming trend with highs
on Sunday in the 60s...warming into the 75-80 degree range by
Wednesday. Showers and thunderstorm chances will re-enter the picture
Wednesday night into Thursday as the ridge shoves east and allows a
trough to approach from the plains.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1208 am CDT Friday may 29 2015

A short wave will produce showers and possibly a thunderstorm
overnight as it moves northeast across the area. Ceilings will
remain primarily VFR at klse and will be MVFR at krst between
29.11z and 29.18z.

Another round of showers will move through the area during the
afternoon and evening. There may be even some scattered
thunderstorms during the afternoon. Ceilings will remain MVFR at
krst...and then lower to MVFR after 29.2230z.

Winds will be southerly through early afternoon and then become
west and northwest at krst between 29.20z and 29.23z.


issued at 318 PM CDT Thursday may 28 2015

Recent heavier rainfall has a few rivers running higher than normal
within their banks. With more rainfall anticipated tonight through
Friday night in the 1-1.5 inch range with locally higher
amounts...some river levels are expected to remain higher than
normal. Flooding is not anticipated at this time...but for those
living near rivers or planning to recreate on may want
to stay tuned to the latest hydrology statements.


Arx watches/warnings/advisories...


short term...das
long term...das

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