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fxus64 kjan 110806 
afdjan 


Area forecast discussion 
National Weather Service Jackson MS 
305 am CDT Sat Oct 11 2008 


Short term...today through Sunday...surface analysis this morning 
shows high pressure over the northeastern states bringing easterly 
surface flow over the arklamiss region. This is expected to continue 
over the arklamiss region over the next couple of days. High 
pressure aloft will strengthen as we move through the weekend. The 
area is generally dry as well with precipitable waters  below an inch only expected 
to rise to around 1.3 inches by Sunday. This should leave a dry 
forecast for the short term. 


Have remained pretty much with mav gui for temperatures through the 
short term. Highs will again be in the lower to middle 80s across 
most of the arklamiss region today. Cloud cover will begin to 
increase from the east for tonight and Sunday as an inverted trough 
now located just off the Georgia/SC coast begins to traverse to the west 
toward the arklamiss region. This will allow low temperatures to 
remain warmer in the lower 60s with highs on Sunday only reaching 
the upper 70s to lower 80s across the eastern half of the County warning forecast area./14/ 


Long term...Sunday night through Friday...the highly amplified 
trough ridge pattern over the Continental U.S. Sunday night will gradually 
transition to near zonal flow by the end of the week. The large 
upper trough over the western Continental U.S. Will ride over the large upper 
eastern Continental U.S. Ridge that will be retrograding to the Gulf of Mexico. 
This will result in warmer than normal temperatures through the 
period with slightly greater rain chances. Normals for this time of 
the year at most sites are in the lower 50s for lows and middle 70s for 
highs. Come Sunday night the remnants of the closed low currently 
off the South Carolina coast will be moving across the Gulf states 
as an open inverted trough. This will result in a slight increase in 
moisture and rain chances from the east Sunday night and Monday. 
None of the models generate much quantitative precipitation forecast over our County warning forecast area as the ridging 
surface and aloft look to remain rather Stout over our region 
despite the weakening trough. By Tuesday the inverted trough will be 
west of our area...the large center of high pressure aloft will be 
over the Gulf states while surface high pressure ridges down the 
Appalachians across our area. The large upper trough will be over 
the northern plains with an associated cold front dropping into the 
Central Plains. Best rain chances Tuesday are expected in the 
northwest and southwest. Afternoon highs Monday and Tuesday will top 
out in the low to middle 70s. There are significant differences between 
the GFS and European model (ecmwf) with the timing of the cold front into our County warning forecast area 
but both models stall the front across our area enhancing rain 
chances for the end of the week. The GFS is more progressive with 
the upper ridge moving south of our area and brings the front in on 
Wednesday. The European model (ecmwf) being slower brings the front in on Thursday. 
By Friday even greater differences in the models occur with the 
European model (ecmwf) featuring a reamplification this time with ridging over the 
west and troughing in the east. The GFS trends to a broad upper 
ridge. The European model (ecmwf) would bring US a reinforcing cold front and rain 
Friday night versus drier weather with the GFS. Will lean toward a 
continuation of warm and mostly dry for now. The proximity of the 
cold front may hold temperatures over our Delta to near 80 degrees 
Wednesday but middle 80 highs area expected again for Thursday and 
Friday afternoons. Greater low level moisture over the County warning forecast area by 
Monday and no frontal passage should hold over night lows in the 60s 
through the period. /22/ 


&& 


Aviation...morning fog and stratus can be expected again this 
morning. This can bring periods of IFR to even LIFR to most sites 
this morning...especially between 09-14z. Any fog should lift after 
sunset. This will leave prevailing VFR flight categories through 
the rest of the day and into the evening. Scattered cumulus with bases 
around 3-6 kft will be possible from late morning through the day 
across the entire region...with possibly a little more cloud cover 
for the eastern half of the region./14/ 


&& 


Preliminary point temps/pops... 
Jackson 84 64 79 66 / 0 0 2 17 
Meridian 83 62 79 61 / 0 0 7 24 
Vicksburg 86 63 82 64 / 0 0 0 11 
Hattiesburg 84 62 79 64 / 0 0 0 17 
Natchez 84 64 81 65 / 0 0 0 8 
Greenville 87 63 82 63 / 0 0 0 14 
Greenwood 86 63 82 65 / 0 0 3 22 


&& 


Jan watches/warnings/advisories... 
MS...none. 
La...none. 
Arkansas...none. 
&& 


$$ 


Short term/aviation: 14 
long term: 22