Summary: Low white and grey stratus clouds looked to cover the whole sky, during the morning, afternoon, evening, and night. The wind speeds looked to be calm with maybe some occasional moderate gusts. Light to moderate and moderately heavy rain with some heavy to really heavy rain persisted from the early morning through the early night in the Houston, TX area and maybe through the late night in some of the Houston, TX areas. It felt cool, during the early morning and evening. It felt a little cool, during the mid and late morning and afternoon. It felt very cool, during the night.
Thoughts: I saw two maybe three skidded out cars on the freeway this morning. Lots of driving through the rain today. I am glad that Houston, TX finally got some decent rain. We have not had much rain in a while. So we really needed it. Some ponding and flash flooding. But nothing severe, or damaging.
Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
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000 FXUS64 KHGX 282335 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 535 PM CST Sat Nov 28 2020 .AVIATION... Another night of low ceilings and reduced visibility with SE TX TAF sites on the east side of a slow moving upper trough and the north side of a developing low over South Texas. Periods of light rain will persist for much of the night with weak isentropic upglide. Removed thunder from the TAFs since instability looks weak. It also appears that the best low level focus for convergence will shift east over the Gulf. Drying should commence between 09-11z as the sfc low scoots toward LA. IFR cigs should begin to mix out early Sunday with a mix of MVFR and VFR ceilings for the afternoon. Wrap around clouds will briefly affect northern TAF sites Sunday aftn. Winds will also increase on Sunday and have added gust groups. 43 && .PREV DISCUSSION... /ISSUED 357 PM CST Sat Nov 28 2020/ DISCUSSION... SHORT TERM [Through Sunday]... It`s quite a sight on WV imagery, as a plume of Pacific moisture interactions with an upper low over the Texas Panhandle to fuel a large, continuous swath of rain over the Texas Gulf Coast today. Fortunately, the rain has largely been light to moderate, with rain rates around or less than a quarter inch per hour in our portion of Southeast Texas. So, while rain continues to pile up slowly, it is not occurring quickly enough to spark any flash flooding concerns. We are already seeing, and will continue to see responses in area rivers and bayous as the ground becomes increasingly saturated and runoff increases with it. However, even here, the relaxed rainfall rates are helping to mitigate riverine flood concerns as well. At the surface, a low pressure center is forming up off the lower Texas coast in the coastal trough zone. Expect it to ride up the coastline, likely a little bit offshore towards Southwest Louisiana through the night. Where the low tracks will be pretty important for continued flooding potential through the night. Right now, it appears that the low will be far enough offshore that the greatest low level convergence, and thus, the heaviest rain, will fall offshore over the Gulf. That`s good! But, it would not take a big left deviation in the low`s track to shove that zone of convergence back over the immediate coast. That`s bad. We`ll have to continue to watch the precise track and the evolution of tonight`s rainfall, and stand ready to make adjustments to the forecast quickly if it becomes apparent that the low is moving closer to the coastline, which could modestly increase our concern for flooding coastward of I-10. ...That`s good (the being ready part, that is). Around or a little after dawn, the surface low will have moved far enough to the northeast that the rain shield will exit stage right, and winds will back to northwesterly as higher pressure moves into the picture from the northwest. This will strengthen the northwest winds and make them gusty. At the same time, an upper trough in the northern stream will dig into the Great Plains, linking up with the exiting Pacific upper closed low. This will create a path for modified arctic air to surge into the region - and though the coldest air will miss us to the east, we are likely to see the strongest cold advection of the season, and will largely fight the sun from a clearing sky to a draw. So Saturday`s high, Sunday morning`s low, and Sunday afternoon`s high are liable to be within about 10 degrees of each other. LONG TERM [Sunday Night Through Saturday]... Not a lot of changes with the expectation of colder weather for this part of the forecast as a series of cold fronts move through the CWA in succession. The first front on Sun night will help to clear these persistent overcast cloud decks...but the colder temperatures should hold until Mon night/Tues morning given the decreased northerly flow and clear skies. Freezing/just below freezing temperatures are going to be likely and Freeze Warnings are probably going to be needed for much of the CWA. As the surface high moves east, onshore winds are set to return Tues afternoon/evening. And then with the next upper low moving down from the Rockies, the tightening gradient will help to draw moisture back into the region from the Gulf. Rain chances will be increasing again by Weds as the upper low tracks across the state. This system should drag the next cold front through the area by Weds night with another period of colder temperatures for the rest of next week. MARINE... Did upgrade the SCEC for the offshore waters to an SCA earlier today given the trends of elevated/gusty winds and building seas from this morning and the likelihood of the coastal low developing near/around the middle TX coast tonight. And as such, the ongoing showers (along with some very isolated thunderstorms) should persist over the near/ offshore waters tonight. In the wake of this system (as it passes to the ENE), a strong cold front should be moving well into the coastal waters tomorrow. Moderate/strong northerly winds should keep SCEC or SCA flags in place through Mon. We`ll also need to monitor the tides for the potential for low water conditions around the bays late Sun into Mon. Brief return of onshore winds are forecast to resume Tues with the next cold front currently on the books for late Weds/Thur. HYDROLOGY... Rain rates so far today have stayed very manageable, mitigating the flash flood threat across the area. However, we`ve still seen 2-5 inches of rain pile up over a broad area, with localized higher amounts. And though our dry conditions have meant a greater amount of that rain could soak into the ground, several more hours of light to moderate rain means runoff should increase. This will likely be seen in levels of area rivers and bayous. For now, only points on the San Bernard River are forecast to rise to action or minor flood stage given the rainfall we`ve seen and what is expected to fall yet. However, we are seeing river levels rise across the area as rain continues to fall. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 50 59 37 52 28 / 70 10 0 0 0 Houston (IAH) 56 62 41 53 33 / 80 30 0 0 0 Galveston (GLS) 61 66 47 55 44 / 90 30 0 0 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...Small Craft Advisory until 6 AM CST Monday 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...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...99 Aviation/Marine...99
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