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View Full Version : Friday 11/12/04 Update from Jeff


ticka1
11-12-2004, 07:01 AM
Hope everybody enjoyed the sun yesterday you may not see it again
until after Thanksgiving.

Pattern shift underway this morning as the US storm track builds into
the SW US and then ejects across the southern US.

Low level stratus deck spreading SSW across the area this morning with
the leading edge rough from College Station to Pearland to Freeport. S
and W of this line skies are clear while N and E skies are cloudy.
Cloud deck will cover most of the area by mid morning and it may be
hard to reach the forecast highs in the low 60's if the clouds hold.

Weekend:
Coastal troughing sets up by late tonight from Matagorda Bay south to
Brownsville. Strong upglide and isentropic ascent begins by early
Saturday morning over the coastal bend. Condensation pressure deficits
are a little high to begin with, but then fall as a 30kt low level jet
transports moisture northward over the cold air dome. Widespread rain
will break out early Saturday over S and C TX. There is some question
as to if a small dry air layer near the surface will keep the rain
from reaching the ground. I think this is possible early, but the
lifting along the isotropes will likely saturate the air mass by
Saturday evening. Guidance is just too warm with temps for highs over
the weekend given the clouds and rain. I do not think highs will get
much above 60 if even that warm.

Next Week:

Surface cold dome is eroded by strong pressure falls over SW TX ahead
of a potent upper trough. Surface warm front will move northward
Monday and transitions the stratiform rain into convective
thunderstorms. The entire area should be warm sectored by late Monday
with the atmosphere becoming increasingly unstable. Thunderstorms will
be possible at any time from late Monday through Wednesday night as
the upper trough moves across. Due to the slow motion and strong
dynamics with this system somebody is going to get a lot of rain.

In addition to the increasing rain chances, a 1043mb high will build
into the Midwest and increase the pressure gradient along the northern
Gulf by early next week. Ekman transports will result in tidal piling
along the coast and seas will approach 7-8 feet by early next week. If
winds stay up and shift to the SE after the warm front passes there
could be some minor coastal flooding especially around Matagorda Bay
next week.

Extended:

After the system depart Thursday yet ANOTHER upper low drops into the
SW US by next Friday. This system should move across next weekend with
another shot at heavy rainfall. The next system drops into the SW by
next Sunday 21st and assults the area right before Thanksgiving. As I
stated the pattern has changed and it appears a relentless parade of
storms will affect the area over the next 2 weeks.

Jeff Lindner

Bozo
11-14-2004, 03:27 AM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
243 AM CST SUN NOV 14 2004

.DISCUSSION...
THE EVOLUTION OF THIS ISENTROPIC RAIN EVENT IS NOT GOING TO PLAN.
STRONG HIGH PRESSURE EAST OF THE REGION CONTINUES TO SHUNT THE
DEEPER MOISTURE AND LIFT WELL WEST OF SE TEXAS. THIS TREND WILL
LIKELY CONTINUE TODAY. MODELS SUGGEST A STRONG VORT APPROACHING THE
AREA FROM THE SW THIS AFTERNOON/EVENING AND THIS IS SUPPORTED BY
WATER VAPOR. AM NOT SURE WHICH FEATURE WILL DOMINATE BUT AM LEANING
TOWARD THE DRY AIR AND SUBSIDENT HIGH. HAVE LOWERED POPS SLIGHTLY
TODAY. HAVE LOWERED MAX TEMPS A FEW DEGREES TO COMPENSATE FOR THE
EXPECTED THICK CLOUD COVER. DIURNAL RANGE IN TEMPS TONIGHT SHOULD BE
MINIMAL AND MODELS SUGGEST RISING TEMPS OVERNIGHT. AM SOMEWHAT
SKEPTICAL AS WINDS REMAIN NE.

THE REST OF THE FORECAST REMAINS A CRAP-SHOOT AS WELL. GENERAL
TROFFINESS REMAINS OVER THE AREA...BUT THE UPPER LEVEL LOW WHICH HAD
BEEN FORECAST TO TRACK ACROSS TEXAS IS NOW FORECAST TO TRACK WELL
NORTH OF THE REGION AROUND THE MASSIVE HIGH CENTERED OVER THE EAST
U.S. THIS SEEMS REASONABLE AS THIS HIGH IS NOT GOING ANYWHERE IN A
HURRY. DESPITE THE TRACK OF THE UPPER LOW...UPPER LEVEL WINDS STILL
BECOME STRONGLY DIVERGENT BY TUES/NIGHT AND EARLY WEDS SO HIGH CHC
POPS STILL SEEM TO BE IN ORDER. OVERALL CONFIDENCE FOR A SIGNIFICANT
RAIN EVENT FOR SE TEXAS HAS DIMINISHED GREATLY. WINDS WILL VEER TO
THE SE BY TUESDAY NIGHT...SO TEMPS WILL MODERATE MID-WEEK BEFORE
ANOTHER COOL DOWN TOWARD NEXT WEEKEND. HAVE LEANED TOWARD THE COOLER
GFS GUIDANCE FOR THE FIRST 48 HOURS. 43