Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Little Rock Arkansas
201 PM CDT Friday Oct 24 2014
Main forecast concerns in this cycle are fog potential tonight.
Then a warming trend over the weekend into early next week. Then a
chance of convection late Monday to middle week with an upper and
surface system to affect Arkansas.
Morning fog did dissipate by noon...and will again include some
tonight with similar weather conditions expected. The upper
trough has moved out of the region to the east...while
upstream...a short wave with some moisture was over the Central
Plains. Have seen some high clouds streaming southeast into Arkansas this
afternoon. Atmosphere remains dry with 12z klzk sounding having a
precipitation water value of 0.63 inches...with only moisture in lower 5k
feet. Quite dry aloft. Surface high pressure is over Arkansas at this
time...with dew point temperatures in the lower 50s. Temperatures were warming
today into the 60s and mainly 70s.
Short term...tonight through Monday night
Mostly clear to partly cloudy skies are expected tonight with
patchy fog again. The weak short wave will bring some high clouds
to Arkansas and limit fog formation. Isolated dense will be possible in
river valleys and isolated normal locations but will no be
widespread enough to delineate in the forecast. Lows tonight
mostly in the 50s. Over the weekend...the upper ridge builds in
over the region as the surface high pressure starts over Arkansas then
shifts more to the southeast and a S to SW wind flow returns to Arkansas. Highs
will reach the 80s...with lows in the 50s to some 60s. Patchy fog
will also be possible in spots. On Monday the upper ridge does
move east as short wave energy begins to lift toward Arkansas. A frontal
boundary also approaches the region...and chances of convection
are back in the forecast for Monday night and Tuesday.
Long term...Tuesday through Friday
New model runs continue to generate a little more quantitative precipitation forecast along a slow
moving frontal boundary that comes in early in the period and sticks
around through Wednesday. Medium range models remain in decent
enough agreement that a blend of solutions will be used in spite of
the new Euro blowing the front moving through faster. Since this is
the first run showing this increased speed...will lean slightly
towards the GFS for now.
Period starts with upper level high pressure centered off the East
Coast of Florida with an open trough in the process of closing off
over the upper Midwest. Associated surface low will be located over
the Upper Michigan peninsula with attendant cold front entering the
far northwest corner of the state.
Front will sag slowly to the south as it runs into the Florida high.
Models now showing decent enough moisture return that probability of precipitation will need
to be bumped into the chance category just about everywhere.
Precipitation chances may be increased somewhat as a weak wave moves
to the north but a wait and see approach will be taken here. The
boundary finally clears the state late Wednesday or early Thursday
taking precipitation chances with it.
Temperatures still expected to be above normal on Tuesday in advance
of the front with readings closer to normal days six and seven. Mex
guidance look reasonable and will generally be accepted.
Preliminary point temps/pops...
Batesville Arkansas 56 82 57 84 / 0 0 0 0
Camden Arkansas 52 83 56 86 / 0 0 0 0
Harrison Arkansas 56 83 58 84 / 0 0 0 0
Hot Springs Arkansas 55 82 58 85 / 0 0 0 0
Little Rock Arkansas 55 83 58 85 / 0 0 0 0
Monticello Arkansas 53 83 57 86 / 0 0 0 0
Mount Ida Arkansas 52 82 55 84 / 0 0 0 0
Mountain Home Arkansas 55 84 55 85 / 0 0 0 0
Newport Arkansas 54 83 57 84 / 0 0 0 0
Pine Bluff Arkansas 52 82 57 85 / 0 0 0 0
Russellville Arkansas 52 83 55 85 / 0 0 0 0
Searcy Arkansas 51 82 55 85 / 0 0 0 0
Stuttgart Arkansas 53 83 58 85 / 0 0 0 0
Short term...59 / long term...56