Frost on my way to work, in northwest Houston, TX, during the early morning.
Northwest Houston, TX, during the early morning.
West Houston, TX, during the early afternoon.
Northwest Houston, TX, during the early evening.
Thoughts: I wasn't able to get write a summary, because I wasn't feeling well in the morning.
Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
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796 FXUS64 KHGX 140211 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 811 PM CST Wed Dec 13 2017 .DISCUSSION... At 800 PM, surface high pressure was located over the eastern Gulf and a weak cold front extended from SW MO into central OK and then into the Texas panhandle. The front will move slowly south overnight and will cross SE TX late Thursday afternoon. Cirrus clouds continue to stream over the area and IR imagery shows the cirrus extending across Mexico and into the Pacific. The trajectory will keep the cirrus moving over the region tonight. A light south flow and the cirrus will likely limit the temperature drop tonight so conditions should be warmer than last night. Tweaked temps and sky grids to match current obs otherwise the rest of the forecast looks on track. Looking ahead, A neutral/slightly negatively tilted short wave trough will move east late Saturday into Saturday night. A surface low will approach Matagorda Bay and rain should develop late Saturday. Showers and thunderstorms look likely on Saturday night as the low moves across the region. 43 && .PREV DISCUSSION... /ISSUED 519 PM CST Wed Dec 13 2017/ AVIATION... VFR conditions are expected through the period. A front will push through the area tomorrow reaching CLL around 18Z and IAH around 23-00Z. 11 PREV DISCUSSION... /ISSUED 407 PM CST Wed Dec 13 2017/ DISCUSSION... Quiet weather for the late week, with a warmer day tomorrow before a cold front tomorrow night chops temperatures back down. The forecast gets much trickier for the weekend with rising rain chances and potential for a coastal low passing through. There may be some outside potential for locally heavy rain or even some severe weather, but that potential is very heavily dependent on an uncertain track for any potential low, and confidence is low. Once that clears out - likely Sunday - look for quieter weather to return next week. NEAR TERM [Through Tonight]... Satellite (and a look out the window) shows copious coverage of high clouds both here and across the corner of Southeast Texas we`re responsible for. This has kept temperatures a little suppressed, and safely under seasonal averages for high temperatures. Tonight, we can probably look for more of the same - on the flip side of today, this should keep temperatures from falling as far, and for now keep most of the entire area above 40 degrees, save for the far northern portion of Houston County where the veil of high clouds is not quite as thick. Still, even there I stay just below 40 degrees, so frost should not be a player overnight unless we get a more significant temp drop. SHORT TERM [Thursday Through Friday Night]... A modestly warmer day is expected tomorrow, mainly in the southwest, but this will be a short-lived trend as a weak cold front is expected to push through the area as well, before stalling offshore tomorrow night. Winds will turn northerly and become a bit gusty overnight, more towards the coast. Rain chances will be nil for inland areas, with precipitable water showing a dry column with values near 0.5 inches. A bit of a different story near the coast, where precipitable water will be more in the 0.75-1.00 inch range Thursday night. By this point the front is already through, but the front will be nearby, there will be sufficient moisture present, and we`ll have the help of being in the right rear quadrant of the upper jet, helping support upwards motion. All in all, think we`ve got a shot at seeing some showers in those coastal areas mainly south of I-10. The best chance of showers will likely be Thursday night, and trail off through Friday as the front sags a little farther away from the coast, taking the best rain potential farther offshore. LONG TERM [Saturday Through Wednesday]... From there, things start to get tricky. There is pretty solid model consensus for the development of a coastal low along the stalled front, which will then move northeastward towards our area. From there, some fairly small, but very important divergences in the model begin to emerge. On the bright side (for us), the Euro brings the surface low ashore near Galveston Bay late Saturday night. There`s a low level jet of 40-50 knots and plenty of moisture to help support rain showers. Some CAPE near the coast would make for some thunderstorm potential. Fortunately, the upper jet is a little out of phase yet, and things don`t get quite lined up for heavier rain until everything has moved to our east late Saturday night. On the other hand, the GFS brings the low in near Matagorda late Saturday night. The same strong onshore LLJ exists, but we`re a little better phased with the upper jet. Again, some CAPE is around near the coast allowing for some thunder. However, now with surface winds significantly backed ahead of the low, we`re now looking at a lot of veering winds and with strong vertical shear, that would make for a low level hodograph that wouldn`t make some low-topped spinners an outside possibility. Perhaps more significantly, the strong onshore flow and dynamics could make for some locally heavy rainfall. So, that largely presents a best and worst case scenario. For perspective, the GEFS members range from a third of an inch of rain to three inches of rain at IAH. For now, have significantly upped PoPs in this area, but have held off on hitting a severity until it becomes somewhat more apparent as to what kind of track we`ll get on this coastal trough/low. Fortunately, things look to clear out relatively quickly. The trend will be towards quieter weather for the first half of the week with a generally dry cold front Tuesday, though there is another shot for showers very near the coast if there`s enough moisture return. MARINE... Tranquil maritime weather pattern through tomorrow...weak westerlies over near 1 to 2 foot seas. An early Friday morning cold frontal passage will increase the likelihood of early day rain turning more showery into the Friday afternoon hours. Offshore winds will strengthen to brief advisory during the morning hours...bays and nearshore water cautions by the afternoon. Advisory level far offshore winds will come down right around Friday sunset. A fairly quiet Saturday as northeasterlies veer around the eastern dial and become onshore by mid day. The approach of a western upper trough will pull up a more moist southwestern Gulf air mass and produce an inverted surface trough. Thus...the weather will become increasingly unsettled going into Sunday as onshore flow strengthens...seas build with likely rain and storm probabilities. 31 FIRE... Regional moisture will remain unchanged through early Friday...or ahead of the next cold frontal passage slated for late Thursday night into the early Friday morning hours. Afternoon minimum relative humidities will fall into the lower to middle 40s the next couple of days. Southwesterly transport will veer northerly Friday with the passing boundary...strengthen to more moderate levels early Friday in the wake of the front. Slow deepening of Thursday mixing depths as it will take surface low 60s to break the stout early morning inversion. 31 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 43 66 41 57 38 / 0 0 10 0 0 Houston (IAH) 45 69 44 55 40 / 0 0 20 10 10 Galveston (GLS) 53 67 49 55 48 / 0 0 50 40 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ Discussion...11
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