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fxus64 klzk 051151 
afdlzk 


Area forecast discussion 
National Weather Service Little Rock Arkansas 
651 am CDT Sat Jul 5 2008 


Aviation... 
scattered showers and thunderstorms are expected again today with 
mainly MVFR conditions. However LIFR conditions are expected in 
the north at hro early this morning with fog reducing visibility 
to 1/4sm. Storms will be along a stationary front on the western 
fringe of an area of high pressure. Storms will be concentrated in 
the east tonight as a short wave moves across. Isolated 
thunderstorms are expected Sunday and high pressure and dry 
weather will return for Monday. 


&& 


Previous discussion... /issued 543 am CDT Sat Jul 5 2008/ 


Update... 
patchy fog has developed across the forecast area and a quick 
update is needed to add it to the zones for a few hours this 
morning. 


Previous discussion... /issued 320 am CDT Sat Jul 5 2008/ 


Short term...today through Tuesday 
not many differences between the models this morning in the synoptic 
scale but the usual differences in the smaller scale features 
continue. Differences should not have a large impact on our sensible 
weather this period and will go with a blend of model solutions this 
morning with a lean toward the more consistent GFS. 


Major features showing up quite clearly on moisture channel imagery 
this morning. Upper flow characterized by western US ridging and 
troffing over the Ohio Valley with northwest flow continuing early 
in the period. The upper trough eventually closes off into an upper 
low by Sunday morning which weakens and pulls off to the northeast 
with upper level ridging returning over the southern Continental U.S. Early 
Monday. Ridge will then be the dominate weather feature through the 
remainder of the period with prevailing westerlies suppressed to the 
northern tier states. 


Latest surface analysis shows nearly stationary boundary extending 
roughly from Blytheville to Fort Smith. Models have the boundary 
possible getting just a little further south before it begins to 
lift out and dissipate by early Sunday. 


Still one more round of convection to deal with as upper impulse 
drops down from the northwest today and expecting a situation 
similar to Friday morning during the Saturday afternoon and evening 
time frame. Models continue to hit a middle level jet maximum moving from 
northwest Arkansas into Louisiana. Believe this feature may be 
underdone by the models and will go above guidance probability of precipitation here. 
Locally heavy rain is a possibility with precipitable waters  in excess of 1.75 
inches during this time frame. Enough moisture and instability 
exists for diurnal type precipitation Sunday afternoon as well but 
only chance to slight chances probability of precipitation can be justified. 


Remainder of the period looks hot and generally dry as upper ridging 
returns to the area. Even diurnal precipitation Monday looks hard to 
come by as airmass be warming and appears capped. Upper level 
impulse approaches late Tuesday which will weaken the ridge just 
enough to warrant chance probability of precipitation across the north and slight chance 
probability of precipitation across the central sections late. 


Temperatures will be warming under the expanding ridge with upper 
80s to lower 90s today and widespread 90s Sunday through Tuesday. 
Overnight lows will hover near 70 degrees area wide. Mav/mex numbers 
look reasonable and are generally accepted. 


Long term...Tuesday night through Friday night... 
models show an upper trough over the plains to start the period... 
poised to move into Arkansas. The trough will move through Arkansas 
Wednesday night through Thursday night. Precipitation chances will 
increase as this trough traverses the state. Best chances of 
precipitation will be Wednesday night. Showers and thunderstorms 
will dissipate west to east Thursday evening. High pressure takes a 
stronger hold on the state Friday and will keep the area dry. 
Temperatures will be near normal through the period. 


&& 


Preliminary point temps/pops... 
Batesville Arkansas 89 69 91 71 / 20 20 20 10 
Camden Arkansas 92 71 93 72 / 30 30 20 10 
Harrison Arkansas 88 68 91 69 / 20 10 10 10 
Hot Springs Arkansas 91 70 92 72 / 20 20 20 10 
Little Rock Arkansas 90 70 91 72 / 30 30 20 10 
Monticello Arkansas 92 71 92 72 / 30 30 20 10 
Mount Ida Arkansas 91 70 93 71 / 20 20 10 10 
Mountain Home Arkansas 88 68 90 70 / 20 10 10 10 
Newport Arkansas 89 69 91 71 / 20 20 20 10 
Pine Bluff Arkansas 91 70 92 72 / 30 30 20 10 
Russellville Arkansas 89 69 91 71 / 20 20 10 10 
Searcy Arkansas 89 69 91 71 / 20 20 20 10 
Stuttgart Arkansas 90 70 91 72 / 30 30 20 10 
&& 


Lzk watches/warnings/advisories...none. 
&& 


$$ 




Aviation...51