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Area forecast discussion 
National Weather Service Houston/Galveston Texas 
556 am CDT Sat Oct 11 2008 


Update... 
sent a quick update to the zones to add patchy fog this morning. 


&& 


Previous discussion... /issued 350 am CDT Sat Oct 11 2008/ 


Discussion... 
pleasant October weekend on tap as troughing over the western US 
drops southeast and east and southeast winds bring increasing dewpoints into 
southeast Texas. Patchy fog should dissipate with the morning heating leaving 
partly cloudy skies - a combination of cirrus from Norbert and cumulus from 
the Gulf. The aforementioned trough will lift out Monday-Tuesday 
into ND/South Dakota while the low off the Georgia coast this morning moves back 
west across the northern Gulf Coast. The Gulf Coast low will bring 
in a deep moist southerly to easterly flow up through 500 mb 
Tuesday and Wednesday over southeast Texas. Model soundings across the area look 
to be well capped Sunday gradually destabilizing Monday and then 
uncapped by late Tuesday with precipitable water nearing 2" and k-index values of 
33. Will continue to carry the 20 probability of precipitation Monday increasing to the 
higher probability of precipitation-40s-for the Tuesday night through Thursday morning 
time frame. Upper ridging to build back over Texas Thursday and could 
bring an end to the rains. GFS has backed off on the frontal 
passage and now holds it up over netx...perhaps clipping the 
Crockett/Groveton areas Thursday before very weak cyclogenesis 
over Colorado tightens up the southeast flow across southeast Texas Friday- Friday night. 
European model (ecmwf) and GFS greatly diverging solutions as fast Pacific flow 
brings short wave that deepens much faster after traversing the northern 
rockies Wednesday night per the European model (ecmwf). Am not convinced of the 
this yet so have followed the GFS for now. 


On a tropical note...continued widespread convection across the 
southern and eastern Caribbean and out near 35-40w 10-15n. Both 
European model (ecmwf)/GFS indicate development in the Caribbean Tuesday and Wednesday. 
45 


Aviation... 
high pressure ridge axis remains in place from the Great Lakes to East 
Texas this morning. This has allowed for calm winds across southeast Texas. Low 
level moisture has increased some with dewpoint temperatures in the low 60s 
so some MVFR fog will be possible this morning. Low clouds are also 
coming off the Gulf so there may be some scattered stratus through the 
morning. Fog should lift middle morning with low cumulus in place for 
the rest of the day. Winds should remain from the east to southeast and less 
than 10 kts. Tonight winds should diminish again with some patchy 
fog possible. 


39 


Marine... 
surface ridge axis will continue to shift over the southeast U.S. Sun into 
Monday. This will keep mainly east winds in place across the northwest Gulf and 
Upper Texas coast. Low seas should remain for today but gradually 
begin to build late Sunday and Monday. Long easterly fetch will 
slowly build seas to moderate levels. This long fetch of east winds 
will support swells from the eastern Gulf Tuesday into Wednesday. Swells 
should build to close to 7ft Wednesday and then gradually subside through 
the end of the week. Winds will remain near 15 kts during this 
time. Possible that conditions may warrant a Small Craft Advisory for Wednesday but that 
will largely depend on swell heights. 


39 


&& 


Preliminary point temps/pops... 
College Station (cll) 87 69 87 69 87 / 0 0 0 10 20 
Houston (iah) 87 69 86 69 87 / 0 0 10 10 20 
Galveston (gls) 83 74 82 76 83 / 10 10 10 20 20 


&& 


Hgx watches/warnings/advisories... 
Texas...none. 
GM...none. 
&& 


$$ 


Discussion...45