Sunday, January 1, 2017

Dec. 31 16

Notes: Big to small, bright white, most bright white mixed with light to dark grey and blueish grey, thick, flat, puffy, low stratus clouds looked to cover the whole sky in northwest Houston, TX during the early morning, afternoon, and evening. Big to small, bright white, most bright white mixed with light to dark grey and blueish grey, thick, flat, puffy, low stratus clouds looked to cover the whole sky in west Houston, TX during the morning and afternoon. Big to small, mostly bright white, some bright white mixed with light to dark grey looked to cover the whole sky in northwest Houston, TX during the night. The wind speeds looked to be calm in northwest Houston, TX during the early morning, afternoon, evening, and night. The wind speeds looked to be calm in west Houston, TX during the mid and late morning and afternoon. It felt cool in northwest Houston, TX during the early morning. It felt cool in west Houston, TX during the morning. It started to feel warm in northwest and west Houston, TX during the early afternoon. It felt warm in northwest and west Houston, TX during the mid and late afternoon. It felt warm in northwest Houston, TX during the evening and night. A huge cluster of light to moderately heavy and maybe some really heavy rain passed over the Houston, TX area during the morning and early afternoon. Light to moderate and maybe some moderately heavy rain passed over my house in northwest Houston, TX during the early morning. Light to moderately heavy and maybe some really heavy rain passed over where I work in west Houston, TX during the mid and late morning and early afternoon. I also think I saw some light sprinkles in northwest Houston, TX sometime during the mid, or maybe late afternoon. I didn't see any more rain after that. I didn't hear and thunder, or hear about any thunderstorms. The showers brought some huge puddles and some possible flash flooding to some areas in Houston, TX during the morning and early afternoon. The streets looked to be dry by the mid-afternoon. I didn't hear about any damages from the showers. There was a dense fog advisory issued for the east side of Houston, TX during the night and maybe morning. I didn't see any fog so I guess it didn't make it to the west side of Houston, TX. There were periods during the day where the sun and sky peaked through the clouds a bit in northwest and west Houston, TX.

Thoughts: We got a lot of rainfall this year! I look forward to the new year. More records to break.


Hazardous Weather Outlook

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
949 PM CST SAT DEC 31 2016

TXZ163-164-176>179-195>200-210>214-226-227-235>238-011300-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
949 PM CST SAT DEC 31 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TONIGHT

AREAS OF FOG ARE EXPECTED TO DEVELOP ACROSS SOUTHEAST TEXAS
TONIGHT. DENSE FOG WILL BE POSSIBLE OVERNIGHT AND TOWARD MORNING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ANOTHER STORM SYSTEM WILL ARRIVE LATE SUNDAY NIGHT AND MONDAY
MORNING WHICH COULD BRING SOME STRONG TO SEVERE STORMS ACROSS
PORTIONS OF THE AREA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MIGHT BE NEEDED FOR PORTIONS OF SOUTHEAST TEXAS
LATE SUNDAY NIGHT INTO MONDAY MORNING.

$$


Area Forecast Discussion 
Issued by NWS Houston/Galveston, TX

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 3839 40 41 42 43 44 45 46 47 48 49 50

000
FXUS64 KHGX 010538
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1138 PM CST Sat Dec 31 2016

.AVIATION.../06Z TAF/
IR satellite imagery continues to show some high cloud cover over
much of SE Texas. Fog and low ceilings are developing across the
area despite higher cloud decks. Thinking for the TAF remains
about the same with the expectation being for ceilings and
visibility to continue to drop to IFR and lower CIGs. there may
even be some areas with dense fog but will continue to monitor for
those trends. Very possible that fog and lower ceilings could hold
until the late morning hours before eroding.

CIGS should drop again tonight into Monday morning across the area
as Gulf moisture increases. A strong short wave trough will
approach the area with a line of storms for Monday morning. Added
mention of VCSH/VCTS for TAFs as there is growing confidence of
thunderstorms forming in the morning hours and quickly moving
east.

Overpeck


&&

.PREV DISCUSSION... /ISSUED 930 PM CST Sat Dec 31 2016/

CLIMATE...
Barring any other rainfall over the next few hours, the first-
order climate sites finished 2016 with above normal rainfall.
Two of the four sites reached their annual rainfall before
December. Rainfall in December helped Galveston and Hobby airport
reach above their normal annual amounts. The other two sites
reached their annual normal rainfall amounts well before December:
the City of Houston did so by the end of August; and College
Station by the end of September. The following table lists the
monthly rainfall and departure for each of the four sites for the
month of December and also the annual rainfall and departure. The
last column shows the percentage of the yearly rainfall as
compared to the normal rainfall.

                        December         2016 Annual     Percent
Site                  Rain    Dep        Rain    Dep    of Annual

City of Houston       3.56   -0.18      60.96  +11.19     122.5%
Hobby Airport         3.69   -0.34      56.82   +2.17     104.0%
College Station       2.77   -0.46      46.79   +6.73     116.8%
City of Galveston    11.08   +7.56      56.50   +5.74     111.3%

40

PREV DISCUSSION... /ISSUED 912 PM CST Sat Dec 31 2016/

DISCUSSION...
The main issue for this update regards fog formation. The SREF
probabilities show the best times for fog will be after midnight.
As of 9:00 PM fog and dense fog was located just northeast of the
forecast area. Currently there is enough uncertainty as to timing
and location to wait in issuing an advisory.

Did tweak the rain chances down over the eastern counties and
marine locations. Otherwise, the current forecast is on track.

40

PREV DISCUSSION... /ISSUED 553 PM CST Sat Dec 31 2016/

AVIATION.../00Z TAF/
Shortwave trough that brought widespread showers and a few
thunderstorms along the coast has moved out of Texas leaving some
lingering cloud cover in its wake. IR satellite imagery shows
cloud cover slowly eroding over the area. Houston terminals and
terminals along the coast may not clear out entirely but look for
some VFR conditions at KCLL/KUTS/KCXO for at least a few hours.

Guidance hits the area hard with low ceilings and fog. TAFs were
adjusted to be more pessimistic with restricted visibility
areawide starting at 06Z. Fog may develop sooner and will adjust
accordingly but this largely depends on how cloud cover erodes or
remains over the area. Rainfall today and wet grounds will support
fog with dewpoints already in the 60s. May need to go with
visibility under a mile for most TAFs with 06z update and fog may
linger well into the morning.

06Z TAF may also need to look at convection for Monday morning for
30 hr IAH TAF. Showers will at least be needed and may look at
timing of organized convection moving into the area.

Overpeck

PREV DISCUSSION... /ISSUED 401 PM CST Sat Dec 31 2016/

DISCUSSION...
The KHGX radar is showing a few lingering showers across
Southeast Texas this afternoon as the region remains underneath a
mid/upper level speed maxima associated with a shortwave trough
crossing the state. Afternoon satellite imagery shows subsidence
in the wake of this shortwave has allowed for skies to scatter out
across parts of North Central and South Central Texas, with the
clearing line having reached College Station as of 3 PM CST. As
the mid/upper level wind speed max shifts over the northwestern
Gulf this evening, inland light rain will taper off with a few
showers developing farther south across the coastal waters. Some
of these showers may even make a run for the Upper Texas
coast/Galveston after midnight but will be too light to cause any
real New Year`s Eve impacts.

The bigger concern for New Year`s Eve celebrations will center
around a weak boundary approaching the region from the north
tonight. Light winds and ample near surface moisture pooling ahead
of this boundary will result in patchy to areas of fog development
this evening and tonight, and a Dense Fog Advisory may be needed
as soon as later this evening. Sea fog may also develop along the
coast early Sunday morning as light westerly winds in the wake of
today`s rain gradually back to the southwest and south, pushing
higher dew point air back across the coastal waters. Otherwise,
expect a cloudy and relatively warm start to 2017 with overnight
lows in the mid 50s to mid 60s.

The first day of 2017 will start out relatively benign, with a
few showers along the coast spreading inland from a combination of
subtle disturbances in the southwest flow aloft translate across
the region and weak warm air advection. High temperatures are
forecast to top out in the 70s. Afternoon water vapor imagery
shows a compact closed low located off the California coast and as
this feature opens into a shortwave trough as it reaches Texas
Sunday night, daytime benign conditions will transition into
nighttime storms for parts of Texas.

Scattered thunderstorms are expected to develop across West
Texas Sunday night, growing upscale into a mesoscale convective
system as the shortwave trough lifts across Texas. Overall timing
for this complex to impact Southeast Texas remains relatively
unchanged (still looking at the 3 AM to noon timeframe on Monday),
but higher resolution guidance (TTU-WRF, ARW, NMM, and NAM12)
offer slightly different placements on path and consequently areas
impacted by this complex. Have greatest confidence in areas north
of Interstate 10 being impacted by the complex, but depending on
the strength of the associated cold pool and any development that
occurs farther south along it may see the thunderstorm complex
extend into the coastal waters as it quickly translates east early
Monday morning.

Environmental conditions still remain favorable for this
thunderstorm complex to produce severe weather. Diffluent flow
aloft, 0-6 km bulk shear values approaching 50-55 knots, and
SBCAPE values approaching 1000-2000 J/kg will promote organized
thunderstorms. Additionally, the associated shortwave trough
taking on a negative tilt as it approaches the ArkLaTex will
resulting in mid- level lapse rates steepening to nearly 7.5 C/km
across parts of Southeast Texas. These steepening lapse rates
raise concerns for a hail threat with the line of thunderstorms.
Also concerned about a damaging wind and an embedded tornado
threat as a 40 to 50 knot low level jet develops, and momentum
transport and speed/directional shear promote the development of
these hazards along the leading edge of the line. Also cannot rule
out at least a locally heavy rain threat with this complex as the
low level jet surges moisture back into the region, allowing
precipitable water values to climb back to near record levels
(around 1.8 inches). However, the anticipated speed of the
complex should prevent more than a minor flood threat from
materializing.

Once the thunderstorm complex clears the region midday Monday,
westerly downslope winds in the wake of the system will allow for
much drier (and warmer) conditions Monday afternoon. Have trended
temperatures above model guidance as a result as MOS tends to
struggle to resolve how warm temperatures will rise in westerly
flow regimes (especially along the Upper Texas Coast). Monday`s
high temperatures will be a struggle between how quickly we clear
out and how much rain falls, but several locations (including
Galveston) may reach or break high temperature records on Monday
as highs are forecast to climb into the mid 70s to near 80. These
drier westerly winds will also result in an end to sea fog chances
along the Upper Texas Coast.

Quasizonal flow will allow for dry conditions to return to
Southeast Texas mid-week as a cold front oozes into the region
late Tuesday into early Wednesday. With poor moisture recovery
behind Monday`s system, expect no precipitation with the front as
it moves across the region but Southeast Texas will see
temperatures fall back to near seasonal normals behind it (highs
in the 60s, lows in the 40s). A second, stronger cold front is
expected to move across the region on Thursday and usher in even
colder weather by the end of the work week. Given differences in
timing with medium range guidance, have opted for a blend of model
temperature solutions in the extended... but with persistent
offshore flow from mid to late week, the light QPF being generated
by overrunning appears to be too aggressive and have trended rain
chances towards the drier side of guidance.

Huffman

MARINE...
Areas of rain with embedded heavier showers and thunderstorms
will continue moving off to the east and out of the area by late
this afternoon or early this evening. Areas of fog (some dense)
can be expected through Sunday morning. The fog could linger
around as onshore winds strengthen and seas build Sunday night and
Monday in response to a storm system moving eastward across the
state. The fog threat should come to an end some time Monday
afternoon or evening as the storms move off to the east and winds
come around to the west. Winds gradually swing around to the
northwest and north Tuesday and Tuesday night, then northeast on
Wednesday. Look for gradually increasing northeast winds and
building seas toward the end of the week. 42

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      56  72  65  75  50 /  10  30  70  70   0
Houston (IAH)              61  74  68  77  53 /  10  30  50  80   0
Galveston (GLS)            65  74  68  79  61 /  20  30  40  70   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Dense Fog Advisory until 9 AM CST Sunday for the following
     zones: Houston...Madison...Trinity.

GM...NONE.
&&

$$

Discussion...40
Aviation/Marine...39

No comments:

Post a Comment