Brittmoore, Houston, TX, early afternoon.
Memorial and Dairy Ashford, Houston, TX, early evening.
Notes: A very warm and maybe sometimes hot and humid day with mostly calm wind speeds. There were scattered showers and maybe thunderstorms in and around the Houston, TX area during the morning, afternoon, evening, and maybe night hours. An isolated shower, or maybe thunderstorm passed near where I work on Brittmoore, during the mid-morning.
Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
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662 FXUS64 KHGX 230301 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1001 PM CDT Thu Sep 22 2016 .DISCUSSION... Showers finally dissipated this evening but not before dumping a good 1-2 inches of rain from near Hempstead to south of College Station. Deeper moisture has returned with the 00z LCH sounding showing 1.7 inches of precipitable water and CRP showing 2 inches. Water vapor imagery shows deepening upper level low over the Great Basin. Upper level ridge remains over much of Texas but has not done much to suppress convection much. After looking at 12z/18z model guidance, here is what we think we know and what we think we don`t know. Models are in pretty good agreement through about 3 days which really isn`t much. Upper low organizes over the Rockies and swings east towards the N Plains by Sunday. Models are good with breaking off a piece of vorticity which drops south into the S Rockies by Sunday. At the surface, a cold front pushes into the plains as the surface low organizes over the N plains. The front then makes slow progress south into Texas on Sunday. Friday through Sunday the boundary layer flow increases off the Gulf of Mexico and moisture continues to increase. Precipitable water values reach 2-2.2 inches Saturday into Sunday. So looks like a good chance of rain Saturday through much of the weekend and early next week. Rainfall amounts will probably be around 1-3 inches areawide for the next 5 days. Considering there are large variability`s between model solutions after Saturday, there are certain details that we don`t know. It is unclear how the upper trough and possible cut off low development evolves. GFS and ECMWF are quite different. This is key because this evolution also determines when the cold front pushes through the area or as the case is with the ECMWF...not push through till much later next week. The front may also be weaker. The other challenge is figuring out the details of where/when any locally heavy rainfall will occur. There are bound to be isolated areas of higher rainfall amounts given storms that could produce high rain rates and strong moisture advection off the Gulf with decent upper level support. But right now it looks like the main axis of heavy rainfall will be more through C TX into OK and E KS. This axis could shift depending on how the trough and upper low evolve. The main point being that it looks like a wet weekend and still have time to monitor forecast data. With the weekend coming up, it would not hurt to prepare and have back up plans in case of heavy rainfall. Overpeck && AVIATION...00Z TAF Still a few pesky showers around north and west, as well as some winds up around 10 kts to start off the forecast period, but both should wrap up pretty early in the evening. After that, clearish skies and lighter winds should prevail for much of the night. Towards morning, sites north look to see light fog and/or some lower clouds. For now, chose to go with some MVFR visibilities, and some clouds, but no ceilings at MVFR levels. Closer to the coast, nocturnal marine showers should push onshore and gradually stream inland into the afternoon. Angled towards VCSH, and kept VFR conditions at SGR and LBX, but there are some second thoughts about that with some potential for similar fog/low clouds. Generally soft-pedaling the guidance here, and banking on a transition from last night being largely VFR through the night towards better potential this weekend. Luchs PREV DISCUSSION... /ISSUED 342 PM CDT Thu Sep 22 2016/ DISCUSSION... Scattered precip will taper off by early evening with the loss of heating. Expect it to regenerate off/near the coast during the late night and morning hours Fri...then expand inland during the day. Similar diurnal scenario will persist Saturday and probably again Sunday...albeit with probably slightly more coverage each consecutive day as moisture levels increase. Forecast from Sunday night into the middle of next week becomes more problematic in regards to the overall pattern which would impact local frontal timing (if any), temps & precip. Not going dive into the specifics regarding different model solutions/scenarios that far out as they`ll change again in the next set of runs. In general, rain chances will increase late in the weekend into early next week as an upper trof & surface front nudge closer to the region. When and where best coverage (and potentially heavier amounts) occur will be dependent on positioning of the trigger and focusing mechanisms described above. Overall forecast confidence is low beyond Sunday. Grids mainly consist of a blend weighted with a higher dose of the slower & warmer ECMWF soln. 47 MARINE... Lee cyclogenesis will allow SE winds to persist through Friday. The low pressure system over Colorado will then move N-NE and drag a cold front into North Texas on Sunday night. There is still some uncertainty with regard to the frontal position on Monday. With the upper flow parallel to the surface front, prefer to follow the lead of the previous fcstr and lean toward a slower fropa for early next week. A weak surface low is expected to develop over the SW Gulf and surface winds will probably become E-NE in response to these systems. Tide levels will probably become slightly elevated early next week in response to the E-NE winds. Deeper moisture over the Gulf and disturbances rotating around abroad upper low over western Mexico will keep showers and thunderstorms in the forecast through early next week. FWIW, both the GFS and the GEM bring the front through on Monday. 43 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 75 93 76 91 75 / 30 40 10 40 20 Houston (IAH) 76 91 77 90 76 / 10 40 10 40 30 Galveston (GLS) 81 90 82 88 81 / 40 40 30 40 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ Discussion...39
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