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Area forecast discussion 
National Weather Service Houston/Galveston Texas
350 PM CDT sun Oct 4 2015

temperatures range from the upper 70s in the Piney Woods to middle
80s along the coast this afternoon. Afternoon water vapor imagery
shows middle and upper level moisture from the remnants of Hurricane
Marty moving into Texas... allowing cirrus to occasionally drift
across the region this afternoon. Also observed on satellite was
upper level ridging over the eastern half of the state... with an
upper low dropping over Southern California and another potent low
located over northern Florida.

High clouds will continue to move overhead tonight as the region
continues to tap into Marty/S moisture and this will inhibit
radiational cooling a bit... keeping low temperatures generally in
the 60s. Forecast soundings differ a bit on coverage and how thick
the high cloud deck will be on Monday... but expect partly cloudy
skies and upper ridging overhead to allow for temperatures a
degree or two warmer than today with temperatures ranging from the
low 80s along the coast to middle 80s inland.

Shortwave ridging is expected to remain in place through
Wednesday before the upper low now over California shifts eastward
towards far West Texas... with temperatures rising into the upper
80s to near 90 inland on Tuesday and Wednesday. Moisture begins
returning as southerly winds resume on Wednesday... with the upper
level flow becoming increasingly diffluent as the upper low
approaches from the west. Both the GFS and NAM generate light quantitative precipitation forecast
as early as Wednesday ahead of this system... but how quickly
moisture returns on Wednesday will be the big limiting factor for
shower development. Forecast soundings do show convective
temperatures being reached over the southwestern counties on
Wednesday afternoon but only covering these areas with a silent 10
pop for now.

Better rain chances for southeast Texas appear to be in the
Thursday through Saturday timeframe as the upper low draws closer
to the region. Medium range guidance is in fairly good agreement
through Thursday and shows the upper low retrograding over
northern Mexico. This will keep highest rain chances over the
western counties /closer to the lift associated with this system/
and the lowest over the eastern counties on Thursday.

Lower confidence with the upper pattern exists heading into
Friday and Saturday though as a northern plains shortwave dives
southeast towards the Mississippi River. The European model (ecmwf) continues
retrograding the upper low... bringing it over Baja California California
Saturday. The GFS opens the upper low Friday and ejects part of it
eastward with the passing shortwave. It also does hang some energy
back... cutting off another low over Baja California California /similar to
the European model (ecmwf)/ over the weekend. Despite this continued uncertainty...
medium range guidance is in good agreement that the passing
shortwave will send a cold front south into the state on Friday.
Persistent diffluent flow aloft and the approach of this frontal
boundary will keep at least low /20-30 probability of precipitation/ in the forecast
through Saturday. Precipitable water values look to range from 1.5
inches over the eastern counties to almost 2 inches over the
western/southwestern counties on Friday... with western counties
expected to see some of the better rainfall during this time.

Increasing moisture and cloud cover will keep temperatures near
to below seasonal normals through the end of the week. Drier
conditions are expected to resume towards the end of next
weekend... with the influence of the upper low well removed from
the region.



light to moderate northeast winds will prevail for the next couple
of days as high pressure lingers over the region. This ridge will
begin to break down late Tuesday or Wednesday as the next upper
level storm system (currently moving into southern california)
begins to slowly move to the east. This pattern change should
allow for a return of more east/southeast winds over the coastal
waters beginning late Tuesday and on into Wednesday. A tightening
pressure gradient could help to produce elevated wind/seas (maybe
near caution levels?) By late Thursday or Thursday night. Rain
chances will also return to the forecast beginning on Wednesday
night and will persist through the end of the week and on into
the start of next weekend. 42


Preliminary point temps/pops...
College Station (cll) 61 86 66 90 68 / 0 0 0 0 0
Houston (iah) 61 84 67 88 68 / 0 0 0 0 0
Galveston (gls) 69 80 73 83 76 / 0 0 0 0 0


Hgx watches/warnings/advisories...



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