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Area forecast discussion 
National Weather Service La Crosse WI
645 PM CDT Thursday may 28 2015

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 00z tafs through 00z Friday evening)
issued at 645 PM CDT Thursday may 28 2015

Mesoscale models continue to slow the movement of the middle clouds and
precipitation into the area this evening. As result...trended
these back by about 2 to 4 hours. Models continue to suggest that
a MVFR deck of clouds will move into the taf sites between 10z and
12z left the timing alone for this. However with
limited instability...delayed the onset of thunderstorms until
after 21z Friday. This would be along threat would be the greatest
along the front.

Am a bit concerned that some of the mesoscale models are suggesting a
break in the precipitation on Friday morning and early afternoon.
Will wait to see whether the 29.00z models show a similar trend
before removing them.


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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