JUNE 2018: Drying Trend & Summer Heat Returns

[srainhoutx]

Andrew, how good is the icon model

Serious Convective feedback issues. Toss it. After a year of watching that German model, I am not impressed at all.

[davidiowx]

Andrew, how good is the icon model

It isn’t very good. I believe yesterday it was showing he heavier rain in northern Mexico and south Texas. It used to be called the GME if I remember correctly. And I never paid attention to it. I’m not a met, but I’ve been watching models and weather for as long as I can remember. I was that kid watching the weather channel, Dr. Neil Frank and others, instead of cartoons lol

[DoctorMu]

Andrew, how good is the icon model

Serious Convective feedback issues. Toss it. After a year of watching that German model, I am not impressed at all.

A daily, focal (locally) scattered showers solution with heavier rain all along the coast seems a lot more probable. There's still a lot of shear running south from the TX/LA border - organization of wave 1 should be negligible.

Area Forecast Discussion
National Weather Service Houston/Galveston TX
319 PM CDT Sat Jun 16 2018

.DISCUSSION...
Scattered showers and very little thunder dot Southeast Texas this
afternoon with temperatures so far mainly in the upper 80s at the
coast to the lower to mid 90s inland. Could see isolated thunderstorm
development before sunset, but most high res models are only showing
showers. Have not made any significant chances to the forecast package
for the next several days. The National Hurricane Center now has
20% formation chances for the Gulf of Mexico tropical disturbance.
As this system moves toward the Texas coast over the next several
days, our area will see significantly increasing rain chances and
the threat for locally heavy rainfall beginning tomorrow and continuing
on through Monday and/or Monday night. Models are showing a variety
of predicted rainfall totals, but for now will stick with Sunday-
Monday totals of 2 to 4 inches with locally higher amounts possible
(higher numbers probably closer to the coast and the lower numbers
probably well inland). Any organization and/or strengthening along
with the eventual track of this currently disorganized system could
result in changes to expected rainfall including a possible risk of
additional heavy rainfall after Monday. For now, generally expect
to see rounds of showers and thunderstorms on Sunday and Monday
when moisture levels and instability are highest, and we`ll keep
rain chances elevated on into Tuesday and Wednesday as precipitable
water values remain close to a 2.0 to 2.5 inch range. Will continue
to carry gradually lowering rain chances for the second half of
week with a lean toward the GFS`s depiction of a mid/upper level
high ridging into the area from the east. 42
&&

.MARINE...
Forecast remains on track to see deteriorating conditions through early next
week as a tropical wave continues to slowly shift west-northwestward over the
western gulf of mexico. Not only will showers and thunderstorms become
more widespread, but winds and seas will also increase Sunday afternoon.
Long-period swell with seas in the 5-7 feet range nearshore and 7-9 feet
range offshore should overspread the area Sunday afternoon and continue into
Tuesday as winds increase into the 20-25 kt range offshore and 15-20 kt in
the bays/inlets. In addition, periods of showers and thunderstorms are
expected as this tropical waves lingers, producing heavy rainfall and
potentially funnel clouds and/or waterspouts. Improving conditions are
expected mid to late week.

Tide levels will increase to between 0.5 and 1.25 feet above normal.
This will lead to some wave run-up or possibly minor coastal
flooding along the Bolivar peninsula Sunday through Tuesday at times
of high tide.

Evans

[srainhoutx]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Sat Jun 16 2018

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Disorganized shower and thunderstorm activity continues in
association with a surface trough over the southern Gulf of Mexico
and an upper-level low over the western Gulf of Mexico. Surface
observations and high-resolution wind data indicate that a surface
circulation does not exist, but strong winds are occuring to the
northeast of the trough. Environmental conditions are not expected
to support significant development, however, heavy rains and gusty
winds are likely to spread across the central Gulf of Mexico tonight
and will reach portions of the Texas and southwestern Louisiana
coasts on Sunday. For more details on this system please see
products issued by your local weather office and High Seas Forecasts
issued by the National Weather Service.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...20 percent.

&&

High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
on the Web at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.

$$
Forecaster Blake

[srainhoutx]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
728 PM CDT Sat Jun 16 2018

.AVIATION...
Forecast challenges this TAF package...possible lowering ceilings
given low level jet and continued advection moisture off the Gulf
and also timing the onset of more widespread showers tomorrow.
Have leaned on model cross sections and convective allowing models
in general scenario of a period of mvfr cigs for coastal taf sites
and the arrival of prevailing showers starting at the coast in the
morning and working inland by midday. For inland TAF sites...CLL
and UTS...more of a tempo MFVR situation tonight and mainly
scattered showers on Sunday. Convection during the day Sunday
appears to have again a strong diurnal component. Bulk of heavier
rain may hold off until Sunday night and Monday with arrival of
tropical wave, trough. DR

[srainhoutx]

Our short fuse meso models are "sniffing" out some deep convection tomorrow afternoon in the NW Gulf. With the last GFS hitting on nocturnal rain storms, HGX is do their best to recognize what our potential sensible weather will be. Challenging forecast ahead...

[stormlover]

Nam is like icon little bit

[unome]

my forecast

better than much of the country:

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
418 AM EDT Sun Jun 17 2018

Valid 12Z Sun Jun 17 2018 - 12Z Tue Jun 19 2018

...Severe thunderstorms and flash flooding continue for parts of the Upper Midwest on Sunday and Monday...

...Continued rain and thunderstorms for the Great Basin and Northern and Central Rockies through Monday...

...Dangerously hot conditions for the Midwest and Ohio Valley on Sunday and the East Coast on Monday...

A slowly moving front stretching from the Midwest through the Plains and into the Rockies and Central Great Basin will be the main weather causer over the next couple of days. For the Midwest and the Plains, heavy rain and severe thunderstorms are likely on Sunday and will persist into Monday. Slight risks of flash flooding and severe weather are in place across the Central Plains into the Upper Midwest on Sunday. An embedded moderate risk of excessive rainfall is in effect for northern Wisconsin and portions of Upper Michigan, where heavy rainfall has already fallen over the past day or so. The eastern part of the front currently in Canada will push southward into the northeastern U.S. by Monday evening, leading to rain and the possibility of flash flooding and strong thunderstorms there as well.

Farther west, an upper-level trough plus the stationary front will lead to rain and thunderstorms for the Great Basin into the Northern and Central Rockies region. Heavy rainfall is possible, particularly for the Northern Rockies, where there is a slight risk of flash flooding in effect on Sunday and Sunday night. Cooler than average temperatures will be in place in those areas.

South of the front, hot temperatures combined with high humidity will lead to heat indices over 100 degrees in the central and eastern U.S. Widespread Heat Advisories are in effect for the Middle Mississippi Valley and portions of the Ohio Valley and Upper Great Lakes region on Sunday. Excessive Heat Warnings are in effect for the cities of Chicago and St. Louis. Heat will build in the Mid-Atlantic and Northeast by Monday, with record high temperatures well into the 90s possible there.

Elsewhere, a trough of low pressure combined with tropical moisture near the Texas coast will produce heavy rainfall there by Monday. There is a slight chance of flash flooding along the Texas coast on Monday, and more rain is expected Tuesday, so continue to monitor subsequent forecasts. Scattered thunderstorms are possible throughout the Southeast through the beginning of the week, but are not expected to be severe or cause widespread flash flooding.

Tate

Graphics available at http://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php

[unome]

a little o/t, but the wicked storms that blew through MN/WI might top our rain totals, they are expecting more today and their radar is out, hope they can get it fixed asap

https://www.weather.gov/dlh/
https://twitter.com/NWSDuluth
https://twitter.com/iembot_dlh

http://weather.cod.edu/satrad/exper/?pa ... rbars=data

[unome]

thorough, local discussion

Code: Select all

523 
FXUS64 KHGX 170934
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
434 AM CDT Sun Jun 17 2018

.DISCUSSION...
Increasingly wet conditions are expected for parts of the region
beginning today and persisting into Tuesday. Forecast rainfall
through Tuesday across the region is generally expected to range 
from 1-3 inches near and north of Interstate 10 to 3-6 inches 
south of Interstate 10. Isolated higher amounts near 8 inches may
be possible closer to the coast through Tuesday, but this will be
dependent on smaller scale features that are difficult to 
anticipate more than a few hours in advance. Dry grounds will 
initially help limit flooding concerns, but the tropical air in 
place will make high rain rates possible. Localized road and/or 
small stream flooding may be possible in areas that experience 
these rain rates or repeated rounds of rainfall through Tuesday. 
Drier conditions are expected by late week for Southeast Texas.

For today... GOES total precipitable water satellite imagery this
morning shows deep tropical moisture has surged as far north as 
the Interstate 10 corridor, with precipitable water values already
at or in excess of 2.0 inches early this morning. Surface and 
satellite analysis place the tropical wave responsible for this 
moisture surge roughly near 25 N, 92.5 W early this morning. An 
associated upper low over the central Gulf will continue to help 
the wave translate towards the Middle Texas coast over the next 
day or so, but rain chances will increase dramatically ahead of 
the wave today with the deeper moisture in place. Regional radars 
already shows speed convergence producing scattered showers  
across the eastern Gulf waters and as temperatures rise into the 
lower to mid 80s later this morning, expect scattered to numerous 
showers with a few embedded thunderstorms to develop inland. The 
KHGX VAD wind profiler has a fairly unidirectional southeast 
profile early this morning and forecast soundings maintain this 
through the afternoon, indicating that any activity that develops 
or moves in from the Gulf will have the potential to train (and 
bump up rain totals). Very high moisture content will make at
least locally heavy rain a possibility with any shower or
thunderstorm today. Some stronger wind gusts will be possible as
well as forecast soundings show a shallow inverted-V signature, 
but with cloud bases anticipated to be lower today think that 
would be a secondary threat if anything at all. High resolution 
guidance for today is fairly consistent in widespread rainfall 
amounts remaining around or under 0.5 inches, with isolated 1-2 
inch amounts where any training occurs. High temperatures were 
trended towards the lower side of guidance today in the mid to 
upper 80s in anticipation of increased cloud cover and higher rain
coverage today.

For tonight... Coastal convergence will keep shower and isolated 
thunderstorm activity persisting through the overnight hours near
and south of Interstate 10, but loss of daytime heating will 
likely cause activity to taper off closer to the Brazos Valley and
Piney Woods regions. Forecast soundings tonight around Houston 
show long, skinny CAPE profiles, which indicates slow vertical
acceleration and increases the residence time of droplets in
clouds. This increases droplet growth and can create the 
potential for increased precipitation efficiency and higher rain 
rates. While speed convergence appears to be the main driver for 
focusing rainfall overnight (likely along the immediate coastal 
counties), have concerns given the orientation of increased near
surface flow (southeast around 25-30 knots) that the land/sea 
interface of Galveston Bay may serve as a surface focus or 
boundary for rainfall tonight and allow some of these higher 
amounts to penetrate into the Houston metro late tonight or early 
Monday morning. Areal totals are still forecast to remain around 
or under 0.5 inches tonight and have only seen an intermittent 
signal for this focusing in higher resolution guidance, but with 
precipitable water values remaining high the heavy rain potential
will continue during the overnight hours and possibly through the
early morning commute. Otherwise, expect overnight lows in the 
70s.

For Monday and Monday night... The highest rainfall for the 
region is forecast for Monday. With almost identical forecast
environmental conditions to today, the big difference in coverage 
will be the proximity of the tropical wave to the region. Modest 
contributions from diurnal destabilization may also help increase
rain totals, which may reach into the 1 to 3 inches range across
the southern two-thirds of the region. Greatest coverage from 
shower and thunderstorm activity is expected to occur along the 
Upper Texas coast, generally from Houston and towards points 
southwest and west. Rain is expected to linger into the overnight 
hours Monday night.

For Tuesday and beyond... The upper low associated with the 
aforementioned tropical wave looks to linger over the Middle/Lower
Texas coasts through Tuesday, dropping south into Mexico by 
Wednesday as an upper trough swings across the Central Plains. 
Heavy rain may persist along the coast Tuesday morning and into 
the day Tuesday, shifting towards the southwest with time as the 
upper low begins to nudge southward. Rain totals on Tuesday may 
range anywhere from 0.5 inches near the Piney Woods to 1.5 inches 
near Matagorda Bay. Medium range guidance begins to diverge during
the mid-week portion of the forecast as the European has been 
intermittently persisting this upper low over Tamaulipas, Mexico 
and continuing to focus heavy rain along the South Texas coast. 
Regardless of how it evolves over Mexico, the departure of this 
weakness will help rain chances begin to decrease during the late 
week period with rain chances becoming more diurnally- 
driven/seabreeze related. Upper ridging looks to build back into 
the region from the east, allowing for high temperatures to climb 
back above climatological normals into the low to mid 90s by this 
weekend.

Huffman

&&

.MARINE...
Marine conditions are still expected to become poor early this 
week as a tropical wave moves into the area, though the worst 
conditions may be a bit slower in coming, focusing more on Monday.
Look for showers and isolated thunderstorms to be more numerous 
today, but generally follow the typical daily pattern, and become 
more widespread into Monday. 

Along with that, look for winds to strengthen to around small 
craft levels this afternoon - first in the offshore, and 
increasingly close to land through the late afternoon and early 
evening. Between the increasing winds and incoming long period 
swell, seas are also expected to increase. Winds may begin to 
slowly diminish on Tuesday, but remain somewhat breezy and keep 
seas elevated - caution flags may be required once the small craft
advisory is let go, potentially lasting late into the week.

Tide levels are already about a foot above normal, and look to 
peak around 3 feet above MLLW at the Galveston Bay Entrance at 
high tide later this morning. This may cause issues in vulnerable 
locations on the Bolivar Peninsula. As the wave passes to our 
south, wave run-up and flooding issues are likely to be worse on 
Monday. Though the most likely forecast again peaks right around 3
feet above MLLW and comes back down to 2.25 feet between tides, a
"reasonable worst case" scenario would keep tidal levels near or 
above 3 feet MLLW all day and a bit into Monday evening before 
coming down. Given the long period waves expected, suspect that we
may see impacts higher than the deterministic surge modeling 
suggests, which is why I point out the higher-end scenario 
tonight. Still not sure how much/if any trouble we'll see beyond 
the Bolivar as even the high-end solutions give us just over 3 
feet MLLW, but do suspect that any coastal flooding issues there 
may be more sustained on Monday. Other coastal areas should also 
continue to follow the forecast for any changes.

Luchs

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      89  74  87  74  85 /  60  30  70  50  70 
Houston (IAH)              86  76  84  75  85 /  70  60  80  60  70 
Galveston (GLS)            85  80  84  80  85 /  70  60  80  80  70 

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION from 1 PM CDT this afternoon 
     through Tuesday morning for the following zones: Galveston 
     Bay...Matagorda Bay.

     Small Craft Advisory from 1 PM this afternoon to 7 AM CDT 
     Tuesday for the following zones: Coastal waters from 
     Freeport to Matagorda Ship Channel TX out 20 NM...Coastal 
     waters from High Island to Freeport TX out 20 NM.

     Small Craft Advisory from 10 AM this morning to 7 AM CDT Tuesday 
     for the following zones: Waters from Freeport to Matagorda 
     Ship Channel TX from 20 to 60 NM...Waters from High Island 
     to Freeport TX from 20 to 60 NM.

&&

$$

Discussion...14
Aviation/Marine...25

[unome]

the bigger picture - what did we do without this satellite ?

night http://weather.cod.edu/satrad/exper/?pa ... colorbars=

day http://weather.cod.edu/satrad/exper/?pa ... colorbars=

ir color http://weather.cod.edu/satrad/exper/?pa ... colorbars=

[unome]

Area Forecast Discussion
National Weather Service Houston/Galveston TX
643 AM CDT Sun Jun 17 2018

.AVIATION...

Not many big changes in this cycle of TAFs. Expectations continue to be for a gradual degradation of conditions. Went a little more optimistic than guidance and trended towards inherited TAFs for the onset of MVFR ceilings, given current appearance on satellite. Only exception here may be for the Houston metro terminals, as there is a patch of thicker cloud here early this morning.

Continue to advertise showers and storms today to be more like an active, typical summer day, and may see shower activity wane some this evening. Focus more on late tonight and tomorrow as the timeframe for more sustained showers tied to the incoming tropical wave. Have not tried to commit too hard to specifics, but instead paint a broad picture of breezy SE winds, MVFR ceilings, and numerous showers and storms that later shifts can flesh out with more specifics.

Luchs

NHC keeping Gulf distrbance at 20/20 in 8AM, still awaiting Discussion: https://www.nhc.noaa.gov/text/MIATWDAT.shtml

[don]

Im getting more concerned about Heavy rain, some of the mesoscale models look pretty aggressive with rainfall amounts.

[cperk]

Man that is one giant blob of thunder storms in the GOM.

[Rip76]

Yes it is.

[FreeportTX35]

I hope it doesn't flood in downtown..i work evenings 2:30 till 10:30 on navigation blvd..how bad is that area known to flood?

[DoctorMu]

The "blob" and sea breeze showers are still hitting some shear, so for today we'll see moderately fast moving scattered tropical showers. Tops are still getting knocked off.

[Cromagnum]

Bring it on. I'm tired of dragging the sprinklers around.

[srainhoutx]

Sunday morning briefing from Jeff: (...sorry for being late getting this posted...been tied up all morning...)

Heavy rainfall possible this evening through Tuesday

Much talked about tropical wave is moving into the western Gulf of Mexico this morning with new flare-ups of deep convection roughly 150 miles ESE of Galveston and over the Bay of Campeche. Satellite derived products and AM soundings from Lake Charles and Corpus Christi indicate that the surge of deep tropical moisture has arrived into the area with PWS of 2.0-2.2 inches south of I-10 and expanding northward. Satellite products show a pool of 2.3-2.6 inches PWS roughly 200 miles SE of the upper TX coast moving toward the NW and this extremely moist air mass will arrive late this afternoon into tonight.

Today:
Scattered tropical showers are already ongoing over the area and once temperatures reach the mid 80’s numerous showers and thunderstorms will develop. Rainfall today should average around .50 of an inch with higher amounts of 1-3 inches under the heavier storms or any storms to may train.

Tonight:
High resolution guidance has a weak signal that is showing up that low level speed convergence will become established near the coast into Galveston Bay as a 30kt low level jet develops over the region of offshore winds of 20-30mph slow to near 10-15 inland of the coast. This will likely help focus lift along the coast starting early this evening and increasing into the overnight hours…especially between midnight and 800am Monday. This appears to be a time period where sustained training or banding of rainfall may occur and thee has been a slight favoring in the short term guidance of the Galveston Bay/I-45 corridor for development. Given the setup…will focus the heavy rains tonight along the coast and into the Galveston Bay area including at least the SE half of Harris County. These trends will need to be monitor throughout the day and into this evening for indications where any training bands may set up tonight.

Monday:
Moisture influx will remain aimed at SE TX with widespread numerous showers and thunderstorms. Much of what transpires on Monday will be a result of how things evolve tonight over the coastal areas…so confidence is lower on where any particular areas could see heavy rainfall on Monday. Air mass will remain very moist and little if no heating will be required to get showers and thunderstorms going.

Monday night-Tuesday:
Moist air mass remains in place over the region with PWS running 2.3-2.5 inches. Will need to focus on Tuesday morning again for potential for coastal speed convergence erupting numerous showers and thunderstorms. This time period may focus the higher rainfall totals closer to Matagorda Bay based on overall moisture transport shifting slowly WSW with time, but cannot rule out additional heavy rainfall across any areas S of I-10.

Rainfall Amounts:
Storm totals today-Tuesday will average 1-3 inches N of I-10 and 3-6 inches S of I-10 with isolated higher amounts of 6-9 inches possible. Higher total will likely focus closer to the coast and near Matagorda Bay and in any areas of sustained cell training. Unidirectional ESE/SE flow through several thousand feet of the air mass support banding and training of cells across the area for the next 24-72 hours. Additionally, with a nearly saturated sounding profile and the tropical nature of the air mass…excessive short duration rainfall rates of 2-3 inches per hour will be possible.

Note: Excessive rainfall of 10-15 inches may focus near the coastal bend/south TX Monday-Wednesday resulting in significant flooding threat.

Hydro:
Creeks and bayous remain near average or below average flow conditions due to the recent dryness and expect the majority of the rainfall to be able to be handled as long as it is spread out over time. Concern will be for those intense short duration downpours which will result in rapid run-off and rises on area watersheds. Grounds will also gradually saturate throughout tonight and into Monday and this will result in increasing run-off over time. Main concern continues to be street flooding versus bayou flooding.

Marine:
Offshore buoys showing long period swells of 7 second arriving into the coastal waters this morning and will landfall on the coast this afternoon. ET surge continues to indicate total water level from wave and tidal run-up reaching 2.5-3.5 feet this afternoon into Monday at high tide. This may cause minor coastal flooding at times of high tide along the Gulf facing beaches on Bolivar. Run-up is already occurring along middle TX coast along Mustang Island.

Forecast 5-Day Rainfall Totals:

[/i]

[Ptarmigan]

https://weather.us/model-charts/euro/te ... 0000z.html

The EURO forecasts up to 28 inches of rain. The GFS forecasts up to 8 inches of rain. The Canadian forecasts up to 16 inches of rain.

ICON
https://www.tropicaltidbits.com/analysi ... 712&fh=168

The ICON forecasts up to 12 inches of rain.