689 
fxus64 kshv 201945 
afdshv 


Area forecast discussion 
National Weather Service Shreveport la 
245 PM CDT Sat Mar 20 2010 


Discussion... 
active weather can be expected over much of the four state region 
through the next 24 to 36 hours. A cold front currently stretches 
this afternoon from east of txk to east of shv to near lfk. 
Widespread light to moderate rain is being observed along and behind 
this cold front. In addition...gusty winds are being observed 
behind the front with a decent pressure gradient expected to 
continue through at least Sunday evening. 


Temperatures are dropping rather rapidly behind the cold front this 
afternoon. Temperatures in northern McCurtain County have already 
fallen to the upper 30s. There is generally a temperature spread 
from the middle and upper 60s east of the front...to the lower 40s 
near tyr. In the meantime...the upper low is expected to deepen as 
it approaches and slowly moves east northeast from the County warning forecast area. While 
the main band of rain is expected to move out of the area...there 
will be plenty of wrap around moisture to move across the area this 
evening and especially overnight. This wrap around moisture will 
combine with rapidly dropping temperatures to bring wintry precipitation to 
portions of the four state region this evening through Sunday night. 
Locations mainly along and north of the Interstate 20 corridor 
should see a wintry mix this evening switch over to 
snow...especially for the Interstate 30 corridor. Locations along 
and north of the Interstate 30 corridor will see the best wrap 
around moisture combined with the coldest temperatures...giving the 
greatest chance of seeing decent accumulations. This area may 
receive around 2-5 inches. Further south to the I-20 corridor...2 
inches or less will be possible...mainly on grassy surfaces. Further 
south...conditions should remain mostly liquid. 


This snow should continue through the overnight hours and into 
Sunday morning. There may be a changeover back to a wintry mix of 
rain and snow for these northern locations on Sunday afternoon into 
Sunday evening as daytime heating allows for a little warming. All 
precipitation is expected to end from southwest to northeast by Monday 
morning as the upper low lifts out of the region. Overall for this 
winter event...a Winter Storm Warning has been issued for locations 
along and north of the Interstate 30 corridor where snowfall amounts 
up to 5 inches will be possible. Also...a Winter Weather Advisory is 
in effect for locations along Interstate 20 and north for light 
accumulations. 


As mentioned earlier...gusty winds can be expected across the four 
state region through the remainder of the day...through the night 
and into Sunday. This is resulting as a tight pressure gradient 
sits over the region with the surface low sitting just to the 
northeast of the four state region. Winds should begin to die down 
Sunday evening as this system gradually begins to lift northeast out 
of the area. 


Conditions will begin to warm up rather quickly as high pressure 
builds into the four state region. Temperatures by Tuesday should 
again begin to approach the lower 70s. Dry conditions will continue 
through middle week as this high controls the weather over the region. 


By Thursday we begin to see our next storm system approach the 
region. A shortwave is expected to approach and move through the 
region Thursday night into Friday...bringing another cold front 
through the region. This will allow for increasing rain chances for 
Thursday through Friday with showers and thunderstorms again 
possible. This activity should move out of the region on Saturday 
to give the area a brief break. /22/ 


&& 


Aviation... 
seasonably strong Southern Plains storm centered in the middle and upper 
levels over central OK this Saturday afternoon will continue to 
deepen and push east through Monday. With this system...a quite 
strong cold front to push east through the mlu and eld areas near 
sunset. 


Surface cold front moving through shv and txk areas as of 1930z this 
afternoon. Expect lowering ceilings to MVFR and even IFR at times 
with the passage of the front and rain. 


By late this Saturday evening...cold front pushes through la and 
Arkansas. In the wake of the front...strong cold air advection and wrap 
around moisture in strong baraclinic storm will result in sleet and 
snow through Sunday morning with continued MVFR or IFR ceilings with 
strong nwrly winds. Also visibilities will lower at times to MVFR with 
snow and sleet across southern Arkansas...NE Texas and northern la. /Viii/ 


&& 


Preliminary point temps/pops... 
shv 33 43 34 59 39 / 70 60 20 0 0 
mlu 37 42 34 55 40 / 90 60 40 10 0 
deq 31 41 35 54 38 / 90 80 30 10 0 
txk 32 40 33 58 39 / 90 80 30 0 0 
eld 33 41 33 57 38 / 100 80 40 10 0 
tyr 32 44 35 59 42 / 60 50 10 0 0 
ggg 32 44 34 61 40 / 60 50 10 0 0 
lfk 32 49 33 63 40 / 40 30 10 0 0 


&& 


Shv watches/warnings/advisories... 
Arkansas...lake Wind Advisory until 7 PM CDT Sunday for the following 
zones: arz050-051-059>061-070>073. 


Winter Weather Advisory from midnight tonight to 4 PM CDT Sunday 
for the following zones: arz060-061-071>073. 


Winter Storm Warning from midnight tonight to 4 PM CDT Sunday 
for the following zones: arz050-051-059-070. 


La...Lake Wind Advisory until 7 PM CDT Sunday for the following 
zones: laz001>006-010>014-017>022. 


Winter Weather Advisory from midnight tonight to 4 PM CDT Sunday 
for the following zones: laz001>004-006. 


OK...lake Wind Advisory until 7 PM CDT Sunday for the following 
zones: okz077. 


Winter Storm Warning from midnight tonight to 4 PM CDT Sunday 
for the following zones: okz077. 


Texas...Lake Wind Advisory until 7 PM CDT Sunday for the following 
zones: txz096-097-108>112-124>126-136>138-149>153-165>167. 


Winter Weather Advisory from midnight tonight to 4 PM CDT Sunday 
for the following zones: txz108>112-124>126-137-138. 


Winter Storm Warning from midnight tonight to 4 PM CDT Sunday 
for the following zones: txz096-097. 


&& 


$$ 


22/08