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Area forecast discussion 
National Weather Service La Crosse WI
632 am CDT Monday Apr 27 2015

Short term...(today through Tuesday night)
issued at 245 am CDT Monday Apr 27 2015

An upper level shortwave trough is slated to slide across northern
portions of the region Tuesday/Tuesday night. Narrow frontogenetic lift with
an associated surface boundary...meager 300-500 mb qg convergence a
loft...and no instability to speak of. Not very dynamic. More
significantly is the dry atmosphere the shortwave will have to work
on. Relative humidity fields hold the deep saturation across southern Canada...with
BUFKIT soundings in the North Point to mostly middle level cloud decks.
Shaping up to be a dry system passage - perhaps some sprinkles.

Long term...(wednesday through sunday)
issued at 245 am CDT Monday Apr 27 2015

Good agreement in the models with shortwave ridging by middle week
giving way to zonal/broad ridging a loft for the weekend. Overall
look is dry until Sat night/sun when the GFS/European model (ecmwf) slide a weak
shortwave trough toward the region...coupled with a fetch of low
level moisture. Areas of showers would be the result. Some thunder
also possible.

That said...Fri-Fri night could see a few showers across the region
as a weak surface front/ripple in the upper level flow slips across the
region. Will hold the consensus solution of slight chances for now.

For temperatures...readings at or above the seasonable normals will
round out April and start off may. Look for 70s at most
locations this weekend.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 632 am CDT Monday Apr 27 2015

Main aviation concerns are wind speeds today. Latest 11z surface
analysis shows high pressure over southern Ontario and northern
Minnesota and latest metars over southwest Wisconsin and southeast
Minnesota reporting northerly winds of 5 to 10 knots. With sunny
skies today and daytime heating...wind speeds of 10 to 15 knots
may mix down from aloft to the surface after 18z today. This is
evident off of the latest 27.06z GFS/NAM/rap BUFKIT soundings at
both rst/lse taf sites. For now...will continue with 8 to 10
knots at both taf sites. With high pressure dominating the area
through taf period...expect VFR conditions to prevail.


Fire weather...
issued at 245 am CDT Monday Apr 27 2015

While the dry - warming forecast for the week is good news for brings some concerns for fire weather
conditions...especially the next couple days.

BUFKIT soundings suggesting good afternoon mixing today/Tue...with
dew points likely falling into the 20s today...and lower 30s Tuesday.
With highs expected to warm into the middle/upper 60s both
days...resulting min humidities will drop into the 20 percents
today...and near 30 Tuesday.

Winds speeds will be a mitigating factor to higher fire
dangers...generally staying 10 kts or less from the North-East.


Arx watches/warnings/advisories...


Short term....rieck
long term.....Rieck
fire weather...rieck

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