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000
FXUS64 KHGX 270100
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
800 PM CDT THU MAY 26 2016

.UPDATE...
Have updated and extended the Flash Flood Advisory for SE TX into
tomorrow afternoon. Line of training storms have persisted across
northern parts of the CWA this afternoon into this evening. There
is concerns with the possibility of more storms tomorrow and this
could further exacerbate our ongoing flood issues. 41

&&

.PREV DISCUSSION...

AVIATION...
A nearly solid line of thunderstorms extends between Cleveland
and Brenham and is slowly drifting to the south toward the KIAH
airspace. I inserted a TEMPO for 3SM TSRA for th enext two hours with
hopes that the main thunderstorms will remain to the north of the
terminal. However, given the poor performance of our available
model guidance, I would not be surprised to see 1/2SM +TSRA within
the next two hours as the line continues to slowly drift to the
south.

A strong southeast flow continues to pump additional moisture in
to the thunderstorm complex while a train of upper level
disturbances and a split flow in the jetstream contribute to
generate sustained lift. It is likely that this system will
continue for the next few hours. We will likelyu get a break during
the early morning hours, however we expect a similar precipitation
scenario on Friday.

Terminals outside of the thunderstorm complex should remain MVFR
overnight. Those affected by the complex will rapidly experience
IFR/LIFR CIG and VIS conditions.                 Keehn

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      73  83  71  88  72 /  70  80  50  40  10
Houston (IAH)              75  85  74  88  73 /  70  70  40  30  10
Galveston (GLS)            78  83  77  83  78 /  40  50  20  20  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch through Friday evening FOR THE FOLLOWING
     ZONES: Austin...Brazos...Burleson...Fort Bend...Grimes...
     Harris...Houston...Liberty...Madison...Montgomery...Polk...
     San Jacinto...Trinity...Walker...Waller...Washington.

     Flash Flood Watch through Friday afternoon FOR THE FOLLOWING
     ZONES: Chambers.

GM...Small Craft Advisory until 4 PM CDT Friday FOR THE FOLLOWING
     ZONES: Coastal waters from Freeport to the Matagorda Ship
     Channel out 20 NM...Coastal waters from High Island to
     Freeport out 20 NM...Galveston Bay...Matagorda Bay...Waters
     from Freeport to the Matagorda Ship Channel from 20 to 60
     NM...Waters from High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...41





000
FXUS64 KHGX 270019
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
719 PM CDT THU MAY 26 2016

.AVIATION...
A nearly solid line of thunderstorms extends between Cleveland
and Brenham and is slowly drifting to the south toward the KIAH
airspace. I inserted a TEMPO for 3SM TSRA for th enext two hours with
hopes that the main thunderstorms will remain to the north of the
terminal. However, given the poor performance of our available
model guidance, I would not be surprised to see 1/2SM +TSRA within
the next two hours as the line continues to slowly drift to the
south.

A strong southeast flow continues to pump additional moisture in
to the thunderstorm complex while a train of upper level
disturbances and a split flow in the jetstream contribute to
generate sustained lift. It is likely that this system will
continue for the next few hours. We will likelyu get a break during
the early morning hours, however we expect a similar precipitation
scenario on Friday.

Terminals outside of the thunderstorm complex should remain MVFR
overnight. Those affected by the complex will rapidly experience
IFR/LIFR CIG and VIS conditions.                 Keehn

&&

.PREV DISCUSSION... /ISSUED 441 PM CDT THU MAY 26 2016/

DISCUSSION...
Large MCS that developed over the northern parts of the CWA earl-
ier this afternoon will be continuing to move E/SE into the even-
ing hrs. Reports of tornadic damage have been largely confined to
Bryan/College Station area but reports of flooding have been more
widespread over Washington, Burleson, Brazos, Grimes, and Madison
counties. Given the current trends, not expecting things to quiet
down until late this evening. Of concern is the track of this MCS
toward Harris county during the next few hrs. Also seeing another
shortwave (per WV imagery) moving in from the W/SW...with an ext-
rapolated timing for this evening. A break from all the action is
progged for the overnight hours.

However...

Models are hitting SE TX with more unsettled wx for tomorrow with
another disturbance moving in from the SW. Upper jet dynamics and
low-level jet structure are progged to be a bit more favorable as
the very moist airmass remains in place. The main uncertainty may
be how unstable/worked over we will be (in the wake of the storms
today). But given how wet the pattern has been have opted to keep
POPS high for tomorrow.

The forecast for this upcoming holiday weekend looks to remain an
active one (though not as active as today/possibly tomorrow). The
seabreeze should be the main focus with daytime heating. Possible
embedded shortwaves within the persistent SW flow aloft could add
more lift (storms) to this scenario. Did lean more heavily on the
ECMWF in the extended. 41


MARINE...
The tight pressure gradient between a deep low over the OK/TX
Panhandles and a high over the southeastern U.S. will maintain a
strong southeasterly flow through Friday. Winds will likely
strengthen to SCA levels early this evening.  seas are running 4 to 6
feet and should increase to 5 to 8 feet on Friday

A persistent fetch from the Western Carribean combined with the
strong on shore flow will raise tide levels to near 3.5 feet above
MLLW on Friday morning. A coastal flood advisory will likely be
necessary on Friday morning`s high tide along the Bolivar Peninsula.

Memorial Day weekend weather will be less active...a 10-15 knot
southeast wind over gradually lowering seas...3 to 4 foot wave
heights by late Saturday night through Sunday PM. Memorial Day will
be tranquil...very low rain chances and a near 10 knot onshore wind
over average 2 to 3 foot wave heights.             44

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      73  83  71  88  72 /  70  80  50  40  10
Houston (IAH)              75  85  74  88  73 /  60  70  40  30  10
Galveston (GLS)            78  83  77  83  78 /  40  50  20  20  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch until 10 PM CDT this evening FOR THE FOLLOWING
     ZONES: Austin...Brazos...Burleson...Fort Bend...Grimes...
     Harris...Houston...Liberty...Madison...Montgomery...Polk...
     San Jacinto...Trinity...Walker...Waller...Washington.

GM...Small Craft Advisory until 4 PM CDT Friday FOR THE FOLLOWING
     ZONES: Coastal waters from Freeport to the Matagorda Ship
     Channel out 20 NM...Coastal waters from High Island to
     Freeport out 20 NM...Galveston Bay...Matagorda Bay...Waters
     from Freeport to the Matagorda Ship Channel from 20 to 60
     NM...Waters from High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...41
Aviation/Marine...44





000
FXUS64 KHGX 261159
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
659 AM CDT THU MAY 26 2016

.AVIATION...
Convective chances will be on the rise through the day. A
shortwave disturbance passing up from the southwest should be the
kicker in producing (primarily afternoon northern hub) scattered
showers and thunderstorms. High resident regional moisture with
decent southeasterly inflow so, as afternoon temperatures approach
the middle 80s, central Texas activity should begin to blossom and
maintain itself into portions of southeastern Texas. Timing is
tricky with western interior activity possibly beginning as early
as late mid to late morning with possible VCTS around metro hubs
commencing after noon or 1 PM. Convective initialization will all
be dependent upon the timing of a disturbance that is modeled to
move out of the valley and travel northeast through East Texas
during peak heating. Periods of VFR ceilings but majority of the
period will be spent at MVFR (occasional IFR up north) with a
persistent 10-15 knot lower level onshore wind. 31

&&

.PREV DISCUSSION... /ISSUED /

DISCUSSION...
Still looking for increasing rain chances across Southeast Texas over
the next two days as a series of disturbances move across the state
and help to ignite shower and thunderstorm development. Best support/
lift/instability for possible strong/severe storms and locally heavy
rainfall still looks to be setting up across parts of our western and
northwestern counties. However, based on a number of different scenarios
being shown by the models, cannot rule out some of this risk (especially
the locally heavy rainfall) spreading further to the east and south
across the rest of our area. The primary severe weather threats will
be locally heavy rainfall (and possible localized flooding) along with
strong/damaging winds, frequent lightning and large hail. Rainfall totals
for this Thursday-Friday event are expected to range from 1 to 2 inches
in and around the coastal counties to 3 to 4 inches across our northwestern
and western counties. Locally higher amounts will be possible area wide.
Looks like less rain over the Memorial holiday weekend with lower rain
chances and warmer temperatures. Look for mainly daytime 20% to 30%
rain chances during the first half of next week as weak upper level
ridging attempts to build into the state from the south. The next upper
level trough moving slowly eastward across the state during the second
half of the week has some potential to getting us back into a wet pattern
as we start the new month.  42

MARINE...
The tightening onshore pressure gradient between a deepening low
over the OK/TX Panhandles and the southeastern U.S. high will
maintain a stout southeasterly wind through the day. Winds will
likely strengthen to caution levels over the western waters this
afternoon...water-wide caution level winds by this evening. This
persistent fetch will magnify to advisory levels overnight early
Friday morning and likely maintain these magnitudes through the late
afternoon. Seas will gradually build from this afternoon`s average 4
to 5 foot heights to 5 to 8 feet by Friday afternoon with a 7 to 8
second period swell. Slight chances for showers or storms today will
increase to low chances over the bays and nearshore waters Friday
with the passage of a stronger shortwave disturbance. A more
pronounced rip current may linger on through late Saturday evening.

Memorial Day weekend weather will be less active...a 10-15 knot
southeast wind over lowering seas...3 to 4 foot wave heights by late
Saturday night through Sunday PM. Memorial Day will be
tranquil...very low rain chances and a near 10 knot onshore wind
over average 2 to 3 foot wave heights. 31

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      82  73  82  71  88 /  70  50  70  50  40
Houston (IAH)              84  75  84  73  88 /  50  40  60  40  30
Galveston (GLS)            82  78  82  78  83 /  40  30  30  20  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...Small Craft Advisory from 1 AM to 4 PM CDT Friday FOR THE
     FOLLOWING ZONES: Coastal waters from Freeport to the
     Matagorda Ship Channel out 20 NM...Coastal waters from High
     Island to Freeport out 20 NM...Galveston Bay...Matagorda
     Bay...Waters from Freeport to the Matagorda Ship Channel
     from 20 to 60 NM...Waters from High Island to Freeport from
     20 to 60 NM.

     SMALL CRAFT SHOULD EXERCISE CAUTION from 4 PM CDT this afternoon
     through late tonight FOR THE FOLLOWING ZONES: Coastal
     waters from Freeport to the Matagorda Ship Channel out 20
     NM...Matagorda Bay...Waters from Freeport to the Matagorda
     Ship Channel from 20 to 60 NM.

     SMALL CRAFT SHOULD EXERCISE CAUTION from this evening through
     late tonight FOR THE FOLLOWING ZONES: Coastal waters from
     High Island to Freeport out 20 NM...Galveston Bay...Waters
     from High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...31
Aviation/Marine...42





000
FXUS64 KHGX 250021
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
721 PM CDT TUE MAY 24 2016

.AVIATION...
Concerns for the 00z TAFs include low stratus development
overnight and isolated showers developing near the inland
terminals Wednesday afternoon.

Southerly to southeasterly winds around 7 to 15 knots are
expected to prevail through the period. Similar to last night,
expect MVFR stratus to develop again overnight and persist into
the late morning hours before beginning to break up/lift to VFR
with daytime heating. May see a few hours of IFR stratus at more
sheltered locations, but confidence was not high enough to include
more than a TEMPO mention in at Conroe and Huntsville.

A few showers may be able to develop again tomorrow afternoon as
convective temperatures in the mid to upper 80s are reached and
the GFS/NAM/ECMWF are fairly consistent in some activity
developing in the late afternoon to early evening hours. Included
a VCSH mention in for the inland terminals for late Wednesday
afternoon but the region looks to remain on the northern periphery
of a mid/upper level ridge and this feature may limit greater
shower coverage during this time.

Huffman

&&

.PREV DISCUSSION... /ISSUED /

DISCUSSION...
Surface dew points were very warm today and heat index values
were closing in on 100 degrees. Warm and humid conditions will
prevail again Wednesday into Thursday. A few showers had developed
this afternoon beneath a weak capping inversion and near a weak
850-700 mb convergence zone. With the loss of heating and the
weakening of the convergence, feel precipitation will come to an
end around sunset. Skies should remain mostly cloudy overnight and
min temps will remain very warm. Upper level ridging will remain
over SE TX on Wednesday but PW values will approach 1.85 to 2.00
inches during the afternoon. The jet structure shows a bit of a
split over SE TX and upper level winds look divergent between
15-21z. Fcst soundings show quite a bit of dry air between 850-600
mb and a weak cap near 700 mb. Have added slight rain chances for
Wednesday due to the high moisture content and favorable jet
dynamics despite the mid level drying/cap.

Forecast soundings show a saturated column developing below 850 mb
on Wednesday night. Could get a few streamer showers beneath the
cap on Wednesday night so will maintain slight rain chances.
Thursday is looking more interesting as PW values surge to near
2.00 inches and a weak short wave moves across SE TX. Upper level
winds will once again split over SE TX and the combination of
these three ingredients should compensate for some slightly drier
air in the 850-700 layer and a weak capping inversion which should
easily erode by 18z. Will stay with chance PoPs for now but likely
PoPs may ultimately be required on Thursday, particularly over the
NW half of the region.

Rain chances should remain high on Friday as a strong and neutral
to negatively tilted upper trough moves east across the Southern
Plains. SE TX will lie in a well defined jet couplet with PW
values near 2.00 inches. CAPE values will be close to 3500 J/Kg
and LI values between -9 and -11 over the northern zones so some
of the storms could become strong to severe over the NW half.
Will maintain likely PoPs on Friday for areas away from the coast
and taper slightly lower toward the coast and over the gulf.

Some uncertainty for the weekend and early next week as global
models diverge in their respective upper air patterns. The GFS
builds a ridge over SE TX Sunday through Tuesday while the
Canadian and ECMWF maintain a weak upper trough and SW flow aloft.
Will maintain slight rain chances Sunday thru Tuesday and will
await models to build a consensus. 43

MARINE...
A moderate on-shore flow will continue for the next several days.
SCEC flags are up for all coastal and offshore waters through 7 AM
Wednesday morning.  Winds may fall below SCEC criteria Wednesday and
Thursday as the axis of the surface ridge shifts to the east,
however the gradient tightens again later in the week, possibly
pushing winds to advisory levels on Friday.  Winds and seas should
gradually subside over the Memorial Day Weekend as the gradient
loosens once again.

The current weather pattern sets up a long fetch to the Western
Carribean.  Tide levels will gradually increase for the next several
days with a Coastal Flood Advisory possible for Friday as the
predicted tide levels near 3.5 feet may cause flooding of lower
lying areas on the Bolivar Peninsula and along Toddville Road in
Seabrook.                                               44

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      74  88  73  81  72 /  20  20  20  50  30
Houston (IAH)              75  88  75  85  74 /  20  20  20  40  30
Galveston (GLS)            78  83  77  82  77 /  10  20  20  30  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Wednesday morning
     FOR THE FOLLOWING ZONES: Coastal waters from Freeport to
     the Matagorda Ship Channel out 20 NM...Coastal waters from
     High Island to Freeport out 20 NM...Waters from Freeport to
     the Matagorda Ship Channel from 20 to 60 NM...Waters from
     High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...31
Aviation/Marine...14





000
FXUS64 KHGX 242045
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
345 PM CDT TUE MAY 24 2016

.DISCUSSION...
Surface dew points were very warm today and heat index values
were closing in on 100 degrees. Warm and humid conditions will
prevail again Wednesday into Thursday. A few showers had developed
this afternoon beneath a weak capping inversion and near a weak
850-700 mb convergence zone. With the loss of heating and the
weakening of the convergence, feel precipitation will come to an
end around sunset. Skies should remain mostly cloudy overnight and
min temps will remain very warm. Upper level ridging will remain
over SE TX on Wednesday but PW values will approach 1.85 to 2.00
inches during the afternoon. The jet structure shows a bit of a
split over SE TX and upper level winds look divergent between
15-21z. Fcst soundings show quite a bit of dry air between 850-600
mb and a weak cap near 700 mb. Have added slight rain chances for
Wednesday due to the high moisture content and favorable jet
dynamics despite the mid level drying/cap.

Forecast soundings show a saturated column developing below 850 mb
on Wednesday night. Could get a few streamer showers beneath the
cap on Wednesday night so will maintain slight rain chances.
Thursday is looking more interesting as PW values surge to near
2.00 inches and a weak short wave moves across SE TX. Upper level
winds will once again split over SE TX and the combination of
these three ingredients should compensate for some slightly drier
air in the 850-700 layer and a weak capping inversion which should
easily erode by 18z. Will stay with chance PoPs for now but likely
PoPs may ultimately be required on Thursday, particularly over the
NW half of the region.

Rain chances should remain high on Friday as a strong and neutral
to negatively tilted upper trough moves east across the Southern
Plains. SE TX will lie in a well defined jet couplet with PW
values near 2.00 inches. CAPE values will be close to 3500 J/Kg
and LI values between -9 and -11 over the northern zones so some
of the storms could become strong to severe over the NW half.
Will maintain likely PoPs on Friday for areas away from the coast
and taper slightly lower toward the coast and over the gulf.

Some uncertainty for the weekend and early next week as global
models diverge in their respective upper air patterns. The GFS
builds a ridge over SE TX Sunday through Tuesday while the
Canadian and ECMWF maintain a weak upper trough and SW flow aloft.
Will maintain slight rain chances Sunday thru Tuesday and will
await models to build a consensus. 43

&&

.MARINE...
A moderate on-shore flow will continue for the next several days.
SCEC flags are up for all coastal and offshore waters through 7 AM
Wednesday morning.  Winds may fall below SCEC criteria Wednesday and
Thursday as the axis of the surface ridge shifts to the east,
however the gradient tightens again later in the week, possibly
pushing winds to advisory levels on Friday.  Winds and seas should
gradually subside over the Memorial Day Weekend as the gradient
loosens once again.

The current weather pattern sets up a long fetch to the Western
Carribean.  Tide levels will gradually increase for the next several
days with a Coastal Flood Advisory possible for Friday as the
predicted tide levels near 3.5 feet may cause flooding of lower
lying areas on the Bolivar Peninsula and along Toddville Road in
Seabrook.                                               44

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      74  88  73  81  72 /  10  20  20  50  30
Houston (IAH)              75  88  75  85  74 /  20  20  20  40  30
Galveston (GLS)            78  83  77  82  77 /  10  20  20  30  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Wednesday morning
     FOR THE FOLLOWING ZONES: Coastal waters from Freeport to
     the Matagorda Ship Channel out 20 NM...Coastal waters from
     High Island to Freeport out 20 NM...Waters from Freeport to
     the Matagorda Ship Channel from 20 to 60 NM...Waters from
     High Island to Freeport from 20 to 60 NM.

&&

$$





000
FXUS64 KHGX 241814
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
114 PM CDT TUE MAY 24 2016

.AVIATION...
Prevailing VFR conditions this afternoon, however some occasional
MVFR ceilings may be possible before 20Z. Widely scattered light
"streamer" showers have developed over much of the CWA. I have
addressed them with VCSH in all of the inland terminals as exact
shower timing would be difficult to pinpoint. Some of the more
reliable short term models suggest that isolated thunderstorms
may also be possible later this around and to the east of the
Houston metro area. I may amend the KIAH and KHOU terminals to add
VCTS around the 21Z update should conditions warrant it.

MVFR cigs are likely to return over night. Model guidance has been
overly pessimistic with cig heights for the last few days so I
leaned more to persistence as guidance. The overall synoptic
pattern will not be much different tonight from last night as SETX
remains pinched between a surface ridge over the Gulf and a
deepening low pressure system on the leeward side of the Rocky
Mountains.                                   Keehn

&&

.PREV DISCUSSION... /ISSUED 1040 AM CDT TUE MAY 24 2016/

DISCUSSION...
At 13z, surface high pressure was located over the SE U.S. with a
trough of low pressure in the lee of the Rockies. The pressure
gradient has tightened and stronger winds expected this afternoon
with conditions becoming breezy. Low level moisture continues to
stream into the area beneath a weak capping inversion near 700 mb.
12z soundings support max temps in the lower 90s but cloud cover
and winds should shave 4-6 degrees from those values. Current
temperature forecast looks on track. There is some weak
convergencenoted in the 850-700 mb layer over the eastern half
of the CWA and this is where both the RAP and HRRR develop some
light showers between 17-22z so bumped pops up to 30 percent over
the extreme east. Rest of the forecast looks on track so no other
changes planned. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      88  74  88  74  84 /  30  10  20  10  50
Houston (IAH)              87  75  88  75  86 /  30  10  10  10  30
Galveston (GLS)            84  78  83  78  83 /  20  10  10  10  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Wednesday morning
     FOR THE FOLLOWING ZONES: Coastal waters from Freeport to
     the Matagorda Ship Channel out 20 NM...Coastal waters from
     High Island to Freeport out 20 NM...Waters from Freeport to
     the Matagorda Ship Channel from 20 to 60 NM...Waters from
     High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...43
Aviation/Marine...44





000
FXUS64 KHGX 241540
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1040 AM CDT TUE MAY 24 2016

.DISCUSSION...
At 13z, surface high pressure was located over the SE U.S. with a
trough of low pressure in the lee of the Rockies. The pressure
gradient has tightened and stronger winds expected this afternoon
with conditions becoming breezy. Low level moisture continues to
stream into the area beneath a weak capping inversion near 700 mb.
12z soundings support max temps in the lower 90s but cloud cover
and winds should shave 4-6 degrees from thos values. Current
temperature forecast looks on track. There is some weak convegence
noted in the 850-700 mb layer over the eastern half of the CWA and
this is where both the RAP and HRRR develop some light showers
between 17-22z so bumped pops up to 30 percent over the extreme
east. Rest of the forecast looks on track so no other changes
planned. 43


&&

.PREV DISCUSSION... /ISSUED /

AVIATION...
MVFR cloud deck to our west is trying to filter into our area
early this morning. Already seeing some of these ceilings (and
even a few IFR level decks) edging into some of our TAF sites.
Expect to have most sites rise from MVFR to VFR later this
morning. Majority of locations should be VFR this afternoon with
possibly gusty south southeast to southeast winds. An isolated
shower or two could develop, but not confident enough to mention
in any TAF sites at this time.  42

PREV DISCUSSION... /ISSUED /

DISCUSSION...
Warm and humid conditions continue this morning with temperatures
in the low 70s and high clouds moving across SE Texas. Latest
surface analysis has weak low pressure in SW Kansas and SE
Colorado. Pressure gradient across SE Texas is not too tight but
still enough to support some light winds this morning. Winds are
stronger offshore in the Gulf of Mexico where 15 knot winds are
common. Water vapor imagery shows an upper level low off the coast
of the mid-Atlantic states. Upper level ridging stretched from SE
Texas towards the Great Lakes. Another upper level low was
organizing over California as a couple lobes of vorticity look to
merge. This system will be responsible for upcoming thunderstorm
chances on Friday.

Today and Wednesday the forecast is very similar to that of
yesterday. There may be a few isolated showers and thunderstorms.
The 00z CRP sounding did show a weak cap from the EML around
750-700mb. Models show upper level ridging building as 500mb
heights increase over the region through Wednesday. This ridging
will be in response to upstream troughing over the Desert SW.
Moisture levels gradually increase today into Wednesday so will
keep mention of an isolated storm in the forecast with 20 PoP.

Upper level low over the southern Rockies slowly moves into the
Plains Thursday into Friday. Timing of the upper low moving into
the Plains has become more consistent between the GFS/ECMWF with a
slow progression and negative tilt on Friday. This means there
will be large scale ascent to weaken capping from the EML. The
upper level jet becomes more favorable with one jet streak
becoming south/north oriented over the Plains placing E Texas in
the right entrance region. Meanwhile the southern branch of the
jet moves across Mexico into S Texas with SE Texas in the left
entrance region. Flow at 850mb increases to around 30 knots off
the Gulf of Mexico and even becomes a bit convergent. Precipitable
water values increase to 1.8 inches on Thursday and then over 2
inches on Friday which is more than previous forecasts. CAPE
should reach 2000-3000 J/Kg across the area combined with decent
low level shear of 10-20kts. Deep layer shear will be increasing
during the day to around 30-40kts. Shear parameters should support
organized convection. The overall pattern along with deep moisture
supports a heavy rainfall threat. Models are really hitting north
Texas hard with precipitation and then bringing higher QPF into SE
Texas late Friday. Most likely axis of heavy rainfall will
stretch from Columbus west of Houston NNE to the Arklatex region.
It is possible for most of the heavy rainfall to be north of
Houston but any mesoscale boundary that develops south of the main
convection could push into the Houston area. It would then be
possible for mesoscale processes to become dominate and given
strong inflow from the Gulf, heavy rainfall could shift farther
south into Houston. Again this is an alternate scenario dependent
on the mesoscale evolution that will be difficult to resolve. On
top of the heavy rainfall threat, severe weather may be possible
given the CAPE/shear combinations. Hail and downburst winds would
be the main hazards but there may be a small tornado threat if
there is enough low level shear.

For the weekend, thunderstorm chances will linger but lower
chances than Friday. While overall moisture decreases with
precipitable water values under 1.7 inches for the weekend, the
atmosphere may still be weakly capped that diurnally driven
convection could still develop. Thunderstorm activity may become
more widely scattered on Saturday with more isolated activity
expected Sunday/Monday.

Overpeck

MARINE...
Winds and seas will continue to slowly strengthen through the week
in response to a tightening gradient between lower pressures in the
lee of the Rockies and higher pressures off to our east. Caution
flags over the offshore waters may need to be expanded these next
few days, and advisories might be needed. Look for decreasing winds
and seas over the Memorial Day weekend.  42

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      88  74  88  74  84 /  20  10  20  10  50
Houston (IAH)              87  75  88  75  86 /  20  10  10  10  30
Galveston (GLS)            84  78  83  78  83 /  30  10  10  10  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through Wednesday morning
     FOR THE FOLLOWING ZONES: Coastal waters from Freeport to
     the Matagorda Ship Channel out 20 NM...Coastal waters from
     High Island to Freeport out 20 NM...Waters from Freeport to
     the Matagorda Ship Channel from 20 to 60 NM...Waters from
     High Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...43





000
FXUS64 KHGX 241121
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
621 AM CDT TUE MAY 24 2016

.AVIATION...
MVFR cloud deck to our west is trying to filter into our area
early this morning. Already seeing some of these ceilings (and
even a few IFR level decks) edging into some of our TAF sites.
Expect to have most sites rise from MVFR to VFR later this
morning. Majority of locations should be VFR this afternoon with
possibly gusty south southeast to southeast winds. An isolated
shower or two could develop, but not confident enough to mention
in any TAF sites at this time.  42
&&

.PREV DISCUSSION... /ISSUED /

DISCUSSION...
Warm and humid conditions continue this morning with temperatures
in the low 70s and high clouds moving across SE Texas. Latest
surface analysis has weak low pressure in SW Kansas and SE
Colorado. Pressure gradient across SE Texas is not too tight but
still enough to support some light winds this morning. Winds are
stronger offshore in the Gulf of Mexico where 15 knot winds are
common. Water vapor imagery shows an upper level low off the coast
of the mid-Atlantic states. Upper level ridging stretched from SE
Texas towards the Great Lakes. Another upper level low was
organizing over California as a couple lobes of vorticity look to
merge. This system will be responsible for upcoming thunderstorm
chances on Friday.

Today and Wednesday the forecast is very similar to that of
yesterday. There may be a few isolated showers and thunderstorms.
The 00z CRP sounding did show a weak cap from the EML around
750-700mb. Models show upper level ridging building as 500mb
heights increase over the region through Wednesday. This ridging
will be in response to upstream troughing over the Desert SW.
Moisture levels gradually increase today into Wednesday so will
keep mention of an isolated storm in the forecast with 20 PoP.

Upper level low over the southern Rockies slowly moves into the
Plains Thursday into Friday. Timing of the upper low moving into
the Plains has become more consistent between the GFS/ECMWF with a
slow progression and negative tilt on Friday. This means there
will be large scale ascent to weaken capping from the EML. The
upper level jet becomes more favorable with one jet streak
becoming south/north oriented over the Plains placing E Texas in
the right entrance region. Meanwhile the southern branch of the
jet moves across Mexico into S Texas with SE Texas in the left
entrance region. Flow at 850mb increases to around 30 knots off
the Gulf of Mexico and even becomes a bit convergent. Precipitable
water values increase to 1.8 inches on Thursday and then over 2
inches on Friday which is more than previous forecasts. CAPE
should reach 2000-3000 J/Kg across the area combined with decent
low level shear of 10-20kts. Deep layer shear will be increasing
during the day to around 30-40kts. Shear parameters should support
organized convection. The overall pattern along with deep moisture
supports a heavy rainfall threat. Models are really hitting north
Texas hard with precipitation and then bringing higher QPF into SE
Texas late Friday. Most likely axis of heavy rainfall will
stretch from Columbus west of Houston NNE to the Arklatex region.
It is possible for most of the heavy rainfall to be north of
Houston but any mesoscale boundary that develops south of the main
convection could push into the Houston area. It would then be
possible for mesoscale processes to become dominate and given
strong inflow from the Gulf, heavy rainfall could shift farther
south into Houston. Again this is an alternate scenario dependent
on the mesoscale evolution that will be difficult to resolve. On
top of the heavy rainfall threat, severe weather may be possible
given the CAPE/shear combinations. Hail and downburst winds would
be the main hazards but there may be a small tornado threat if
there is enough low level shear.

For the weekend, thunderstorm chances will linger but lower
chances than Friday. While overall moisture decreases with
precipitable water values under 1.7 inches for the weekend, the
atmosphere may still be weakly capped that diurnally driven
convection could still develop. Thunderstorm activity may become
more widely scattered on Saturday with more isolated activity
expected Sunday/Monday.

Overpeck

MARINE...
Winds and seas will continue to slowly strengthen through the week
in response to a tightening gradient between lower pressures in the
lee of the Rockies and higher pressures off to our east. Caution
flags over the offshore waters may need to be expanded these next
few days, and advisories might be needed. Look for decreasing winds
and seas over the Memorial Day weekend.  42
&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      88  74  88  74  84 /  20  10  20  10  50
Houston (IAH)              87  75  88  75  86 /  20  10  10  10  30
Galveston (GLS)            83  78  83  78  83 /  10  10  10  10  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION through this evening FOR THE
     FOLLOWING ZONES: Waters from Freeport to the Matagorda Ship
     Channel from 20 to 60 NM...Waters from High Island to
     Freeport from 20 to 60 NM.

&&

$$

Discussion...43
Aviation/Marine...42





000
FXUS64 KHGX 240506
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1206 AM CDT TUE MAY 24 2016

.AVIATION...
Kept with the same general trends with the 06Z TAFS. High cloud
blow-off from storms across west TX are expected to move off to
the E/SE overnight. Once these clouds move out, we should see a
return of MVFR CIGS across most of SE TX the rest of tonight in-
to the early morning hours. These low clouds to mix out by mid/
late morning with mostly BKN CU (but VFR) for the afternoon. We
will likely see a repeat of this pattern tomorrow eve/night. 41

&&

.PREV DISCUSSION...

UPDATE...
Current forecast in good shape, and only a few changes were needed
to account for current conditions. Overnight lows in the lower 70s
expected away from the immediate coast with little or no rain
chances overnight.

Evans

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      74  89  74  84  72 /  10  10  10  60  30
Houston (IAH)              76  89  75  85  74 /  10  10  10  40  30
Galveston (GLS)            78  83  77  82  77 /  10  10  10  20  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 7 AM CDT this morning
     FOR THE FOLLOWING ZONES: Waters from Freeport to the
     Matagorda Ship Channel from 20 to 60 NM...Waters from High
     Island to Freeport from 20 to 60 NM.

&&

$$

Discussion...99
Aviation/Marine...41





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