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Area forecast discussion...updated 
National Weather Service Little Rock Arkansas
550 am CST Monday Feb 8 2016

Discussion...

Updated for the 12z aviation discussion below.

&&

Aviation...

The main concern for the 12z taf period will be the gusty
northwest winds. Persistent gusty northwest winds will exist
through at least 00z for all terminals. Have gusts to almost 30kt
in at all sites by middle morning. Would not be surprised to see some
gusts above 30kt...but expect those to be infrequent. Winds should
begin to ease significantly after sunset and have this accounted
for the in the forecast. The only clouds to speak of will be some
broken-ovc050 ceilings up north...with possibly some scattered-bkn050
bases as far south as klit in the afternoon. Could also see some
very light rain or even snow flurries up north this morning
also...but these should be isolated and very brief and have left
this out of the northern tafs as a result.

&&

Previous discussion... /issued 353 am CST Monday Feb 8 2016/

Short term...today through Tuesday night

Main concerns in the short term will be the winds today...and the
fire weather concerns outlined in the fire weather section below.

Water vapor imagery shows a very strong upper low off the middle
Atlantic coast this morning...with a jet streak dropping south
across Arkansas. The jet streak is part of a leading shortwave
that will usher in a synoptic scale trough...set to establish
itself across the eastern half of the lower 48 by this evening.
This jet streak and associated shortwave will yield some cloud
cover over the northeastern half of Arkansas today...and even some
light precipitation. Do not believe there will be measurable
precipitation in the forecast area today so have lowered probability of precipitation
accordingly. However...regional radar imagery does show some light
returns so my confidence in their being an occasional snow
flurry or sprinkle of rain is high enough to mention in the
forecast.

The main story for the short term though will be the strong winds
expected today. The latest high resolution guidance suggests that
winds will be a little stronger than previously expected. Areas in
the higher terrain of northern and western Arkansas...and also in
the Delta Region south of I-40...will see wind gusts in the 35-40
miles per hour range today. As such...have upgraded the lake Wind Advisory to
a Wind Advisory for today as a result. Model soundings suggest
the mixed layer should deepen to around 4500 feet above ground level. Given the
forecast winds within that layer...it would not be surprising to
see wind gusts above 40 miles per hour to be seen. The most likely place for
these gusts will be in the southwest where better mixing will be
present.

Long term...Wednesday through Sunday night

Overall rather benign...albeit chilly...conditions are expected
through the period. Models are in very good agreement early on
before diverging as the period ends. As such...will blend forecast
solutions this morning.

Period starts off with a highly amplified upper pattern in place
characterized by strong upper ridging over the western United States
and deep troughing over the east. In between these features is a
pronounced northwest flow aloft that sits squarely over the middle
south.

Flow does lose some of its amplitude with time but the same general
pattern remains in place through the period. Models continue to move
several weak systems through but offer very little in the way of
precipitation chances due to lack of significant moisture return.

A front at the end of the week will bring a slight reinforcing shot
of cooler air but this feature does appear to decay somewhat before
reaching the state. Biggest difference in the period shows up Sunday
night and into early Monday as European model (ecmwf) swings a trough through while
the GFS has no sign of it. A slight chance of probability of precipitation will be
introduced to round out the period as a result. Will also try to
blend numbers as well through the period.

Fire weather...

Forecast highs today are on the cooler side of guidance. Given the strong
cold air advection across the region...expect that temperatures
will have a harder time climbing than perhaps models would
suggest. However...it should be noted that if temperatures do climb
higher than expected...that afternoon relative humidity values could be notably lower
than forecast. The significance of this is that winds will be more
than adequate for red flag warning conditions...so if relative
humidity drops to critical levels then the combination of strong
winds...low afternoon relative humidity...and very dry fuels will yield
conditions favorable for explosive fire growth. For now...have
foregone the issuance of a red flag warning as relative humidity values are not
forecast to drop low enough. A Fire Danger Statement /rfdlzk/ has been
issued to address these concerns. Please refer to that product for
further information.

&&

Preliminary point temps/pops...
Batesville Arkansas 41 25 41 23 / 10 10 0 0
Camden Arkansas 48 30 49 31 / 0 0 0 0
Harrison Arkansas 37 23 38 20 / 10 0 0 0
Hot Springs Arkansas 45 28 47 29 / 0 0 0 0
Little Rock Arkansas 45 28 46 27 / 10 0 0 0
Monticello Arkansas 47 29 47 30 / 10 0 0 0
Mount Ida Arkansas 44 28 46 27 / 0 0 0 0
Mountain Home Arkansas 37 24 38 21 / 10 10 0 0
Newport Arkansas 40 26 41 22 / 10 10 0 0
Pine Bluff Arkansas 45 28 46 28 / 10 0 0 0
Russellville Arkansas 44 27 45 26 / 10 0 0 0
Searcy Arkansas 42 26 43 24 / 10 10 0 0
Stuttgart Arkansas 44 28 44 26 / 10 10 0 0
&&

Lzk watches/warnings/advisories...
Wind Advisory until 6 PM CST this evening for Arkansas-Baxter-
Boone-Bradley-Calhoun-Clark-Cleburne-Cleveland-Conway-Dallas-
Desha-Drew-Faulkner-Fulton-Garland-Grant-Hot Spring-Independence-
Izard-Jackson-Jefferson-Johnson-Lincoln-Logan-Lonoke-Marion-
Monroe-Montgomery-Newton-Ouachita-Perry-Pike-Polk-Pope-prairie-
Pulaski-Saline-Scott-Searcy-sharp-stone-Van Buren-white-Woodruff-
Yell.

&&

$$



Aviation...64

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