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Area forecast discussion 
National Weather Service Little Rock Arkansas
600 PM CST Monday Mar 2 2015

Aviation...
widespread IFR to LIFR conditions are expected through the period
as low level moisture remains abundant. A storm system will
approach the region with precipitation becoming likely across the
northern taf sites with possible thunder. Tempo group for rain will
suffice for now for the remainder of the taf sites with convection
becoming prevelant after the period. Light winds initially will
become southwest with time.

&&

Previous discussion... /issued 240 PM CST Monday Mar 2 2015/

Discussion...

Main concerns in this forecast cycle are the middle week system that
will bring more winter weather across Arkansas...short term clouds and
rain chances...then very cold again Thursday and Friday as the
Arctic high pressure settles in over the region with continued
well below normal temperatures. Current Winter Storm Watch was updated to
add general snow and ice amounts and starts on Wednesday.

Skies were cloudy with isolated light rain or light showers. Most
of the rain had moved east this afternoon as the short wave pushed
east. Temperatures were running 10 to 20 degrees below normal. Upper
ridging was seen over the Western Plains and this will move in for
Tuesday with warmer temperatures back closer to normal values...but only
for a day. Tonight to Tuesday...do expect a warm front to lift
over Arkansas and keep a low chance of light rain and light showers over
Arkansas.

Short term...today through Thursday night

Tonight will keep small chances of rain in the forecast with the
expected warm front to gradually lift northward. Some areas of fog
will also be possible. Temperatures tonight wil remain above freezing
therefore only rain is forecast. Most uncertainty is with the
Wednesday to Thursday forecast with rain starting...then colder
air filters in over Arkansas from the north with a cold front...and then
the liquid precipitation will transition to winter weather. This will
take place from north to south as the cold air filters in. Latest
sounding data...conference call with surrounding offices and with
coodination with NCEP winter group...have add more freezing precipitation
especially to central and most in southern Arkansas. The main areas of
snow are expected over northern and central Arkansas. Models are coming
together and showing quantitative precipitation forecast values of 0.75 to over an inch in a 24
hour period...which will bring signficant amounts of winter
weather. At this time...general amounts of snow will be 2 to 4 inches
with locally higher amounts...especially in northern to NE Arkansas. 1
to 2 inches over southern Arkansas. Icing amounts will be around a tenth
north...a tenth of two central...while a few tenths to around a
quarter inch with higher amounts over southern Arkansas. Temperatures on
Thursday and Friday will be very cold with some records possible.
Lows will be in the teens and 20s and highs in the 20s to 30s.
A bit warmer Friday but still well below normal values.

Long term...Friday through Monday

During the extended term the models are having a very difficult
time handling the pattern across North America...as a split flow
regime develops across the western US. During the short term the
storm system that will be bringing snow to US will shear off from
a trough in the southwest...and the remains of the sheared off
trough will be upstream of Arkansas and will ultimately be a key
factor in any weather that affects the area.

European model (ecmwf) and Canadian model want to spin off a closed low and hold it
somwhat stationary across northwestern Mexico...while the GFS tries to bring
it eastward fairly quickly...transitioning it into a shortwave
reaching the local area on Friday night or Saturday. European model (ecmwf) and CMC
are both more conservative at kicking the low out and bringing it
eastward. At this time I am going with more of a blend of the CMC
and European model (ecmwf) and bring just a very slight chance for precipitation to
the southern zones on Sunday...although my confidence in this
solution is somewhat low...so as the models start to hone in on a
solution this may ultimately need to be adjusted.

&&

Preliminary point temps/pops...
Batesville Arkansas 37 57 35 36 / 30 70 70 90
Camden Arkansas 40 66 57 57 / 30 50 80 90
Harrison Arkansas 35 56 26 27 / 30 60 50 80
Hot Springs Arkansas 38 61 47 47 / 30 60 70 90
Little Rock Arkansas 38 62 45 45 / 30 60 80 90
Monticello Arkansas 40 66 58 58 / 40 50 80 100
Mount Ida Arkansas 38 60 45 45 / 30 70 70 90
Mountain Home Arkansas 35 56 29 30 / 30 60 50 80
Newport Arkansas 38 59 36 37 / 30 70 70 90
Pine Bluff Arkansas 38 64 53 53 / 30 60 80 90
Russellville Arkansas 38 57 40 40 / 30 70 60 90
Searcy Arkansas 37 60 40 40 / 30 70 80 90
Stuttgart Arkansas 37 61 44 45 / 30 60 80 90
&&

Lzk watches/warnings/advisories...
Winter Storm Watch from Wednesday morning through late Wednesday
night for Baxter-Boone-Fulton-Independence-Izard-Jackson-Marion-
Newton-Searcy-sharp-stone.



Winter Storm Watch from Wednesday afternoon through late
Wednesday night for Cleburne-Conway-Faulkner-Garland-Johnson-
Logan-Lonoke-Monroe-Montgomery-Perry-Polk-Pope-prairie-Pulaski-
Saline-Scott-Van Buren-white-Woodruff-Yell.



Winter Storm Watch from Wednesday evening through late Wednesday
night for Arkansas-Bradley-Calhoun-Clark-Cleveland-Dallas-Desha-
Drew-Grant-Hot Spring-Jefferson-Lincoln-Ouachita-Pike.

&&

$$



Aviation...56

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