West Houston, TX, during the mid-afternoon.
Northwest Houston, TX, during the mid-afternoon.
Houston, TX radar, during the late afternoon.
Northwest Houston, TX, during the late evening.
Northwest Houston, TX, during the early night.
Locations: Northwest and west Houston, TX.
Thoughts: The rain looked to have started sometime during the evening and maybe continued on through the late night. It was really windy, cold, and very wet, during the night. I am still not feeling that well and am in need of some good sleep, until I can feel well enough to write a full weather report.
Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
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000 FXUS64 KHGX 170218 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 818 PM CST Sat Dec 16 2017 .UPDATE... As of 8 PM local time, looks like the center of the low is inland over Matagorda County with storms right near the center starting to get their act together. Dewpoints right out ahead of this feature at Bay City have climbed to 60 degrees, with 68 degree dewpoints just offshore. Strong inflow is also occurring, with the KHGX VAD wind profile showing 50 knot SE winds at 3,000 feet. Could still see some isolated tornadoes along the coastal counties with this system over the next few hours. Gusty winds are also possible, and we`ve already had some 20-30kt gusts measured across the coastal counties in the inflow region and right on the backside of the surface low. These storms are moving pretty quickly, so the severe threat should be over with for our area by around midnight. 11 && .PREV DISCUSSION... /ISSUED 547 PM CST Sat Dec 16 2017/ AVIATION [00Z TAF Issuance]... Yesterday we knew the next 6 to 9 hours will be a messy aviation forecast and it looks like the forecast is on track with that scenario. Surface analysis has a coastal low pressure forming off the middle Texas coast with a warm front extending east just off the Upper Texas Coast. Upper level trough remains west of the area with water vapor imagery showing a strong vorticity max moving out of Mexico in south Texas with the main upper low centered over west central Texas. Over the next 6 hours we expect ceilings to continue to decrease into MVFR and then IFR categories from 02-05Z. This also corresponds to when showers and thunderstorms will be most numerous. Thunderstorm activity may be confined to KLBX and KGLS but cannot rule out elevated thunderstorms for the Houston metro terminals. KCLL/KUTS/KCXO can expect a broad area of moderate rain for much of the next 6 hours. System should move east out of the area 06-07Z but low ceilings and visibility may remain. Model guidance keeps low ceilings in place for much of Sunday morning with improvement by afternoon. With wet grounds, light winds and a cool airmass, this seems reasonable. Look for TAF amendments based on convection through the next 6 hours to convey the latest timing. Overpeck PREV DISCUSSION /Issued 401 PM CST Sat Dec 16 2017/... A complicated forecast continues to unfold for Southeast Texas as a series of upper level disturbances cross Texas over the next week. The first disturbance is noted on afternoon water vapor imagery lifting across Southwest Texas from Mexico, with a coastal low having developed in response near the Texas Coastal Bend. Little has changed in the forecast thinking through tonight regarding the evolution of this feature, with the surface low lifting up the coast towards Matagorda Bay and then into the Sabine Pass tonight. Light to moderate rain across the northern counties this afternoon will spread south towards the coast in response to enhanced convergence from the low this evening, with a line of showers and thunderstorms sweeping across the region from west to east as the parent storm system ejects towards the Midwest. VAD wind profilers from Corpus Christi show southeast to south winds above 2000 feet and expect more of a northerly movement to the surface low within the next few hours. This would begin to shunt some of the moisture near the low into the Upper Texas coast (dew points in the 64-68 degree range) and increase the potential for a few surface-based thunderstorms. SPC Mesoanalysis shows 0-1 km shear values in the vicinity of this surface low have already increased into the 20-30 knot range (more than sufficient low level rotation to support tornado or waterspout development) and expect an isolated tornado/waterspout potential to increase for the coastal waters and immediate coastal areas within the next few hours. The speed of the overall system should limit any widespread flooding threat with this rainfall, but widespread rain amounts of 1-2 inches will be possible. Expect the line of thunderstorms to clear the region 1-2 AM with the potential for some patchy fog development across the western counties behind the line as the surface pressure gradient slackens. The next system to impact the region is currently in the process of closing off near Baja California this afternoon and will ensure that the region maintains southwest flow aloft in the wake of tonight`s system. Moisture behind tonight`s storm system is never fully scoured out of the northwest Gulf and east to southeast winds becoming reestablished on Sunday will draw this moisture back into the region. This will mean that smaller disturbances moving across the region in the flow aloft will result in periods of showers and thunderstorms spreading into the region from the Gulf beginning Sunday night. Rain chances continue through late Tuesday into Wednesday as the Baja closed low translates eastward and crosses Texas. This looks to drag another cold front across the region and end rain chances for a brief period of time during the mid-week period. A second, stronger cold front is expected to enter the state late Thursday into Friday. Warm air advection ahead of this front may result in light rain spreading inland from the Gulf on Thursday, with a combination of isentropic upglide and mid/upper level forcing from another disturbance west of the region resulting in periods of rain continuing into the upcoming weekend. Much colder air is expected to move into the region behind this cold front, with high temperatures on Friday almost 20 degrees cooler than Thursday. Huffman Long Term Discussion... Speculation continues about the forecast for the weekend before Christmas. CIPS Extended Analogs have shown a consistent signal for sub-freezing temperatures to reach at least parts of Southeast Texas sometime during the December 24 through December 26 timeframe... and this increases confidence that the region will see a spell of much below normal temperatures around Christmas. What remains more uncertain though is when this cold air will actually reach the region. This airmass looks to originate over western/northwestern Canada before being dislodged southward towards the Great Plains as a disturbance now near the Bering Strait also dives south. These polar airmasses tend to be very shallow by the time they reach Texas, which means that model guidance can struggle with when the coldest temperatures arrive behind the initial cold front. This is because the airmass behind the front moves moreso from propagation due to density differences at the surface than forcing from higher up in the atmosphere. The medium range guidance that was inspected today continues to shows signs of that struggle with the deterministic GFS/European not bringing in sub-freezing surface temperatures until Christmas and the Canadian, well, doesn`t bring them into the region at all. This is further compounded by the signal that at least a weak over-running regime sets up across the region behind the front. This over-running, where more warm, moist air is lifted over the colder, shallow post-frontal air, looks to produce periods of light to moderate precipitation across the region over the weekend before Christmas and into Christmas week. Not only is the timing for arrival of colder temperatures in question, but whether or not the atmosphere will be precipitating when they arrive is too. So what do we know? - It will be colder than normal the weekend before Christmas into the beginning of next week. - Winter weather could certainly be possible... but several things have to come together for that to be the case. - It is too early to determine impacts, if any. - Model guidance is still in poor agreement on what will actually happen in that portion of the forecast. This makes forecast confidence low. - Forecast confidence probably won`t begin to increase until the middle of next week when the disturbance near Alaska begins to dislodge our next round of colder air. Huffman MARINE... A Small Craft Advisory is currently in effect across the coastal waters and Matagorda Bay, with easterly winds sitting around 20 kts. A SCEC is in effect for Galveston Bay until 00Z this evening, as winds hover between 15 to 20 kts. As the coastal trough continues to slide up the northern Texas coastline, winds in Galveston Bay will also increase in speed, and a Small Craft Advisory will be in effect beginning at 00Z Sunday. Wave heights will also rise and 4 to 7 feet with this system, as it moves through the coastal waters during the overnight hours. Scattered to numerous showers and thunderstorms will fill in across the waters later this afternoon into the early evening hours as the coastal low slides north/northeast. This activity should continue until shortly after midnight when this system shifts eastward. Embedded in these showers and thunderstorms will be the potential for gusty winds and isolated waterspouts through early Sunday morning. Wave heights will begin to lower Sunday afternoon to between 2 to 4 feet, and onshore flow will return. With winds out of the east/southeast, warm moist air will flow over cooler shelf waters and periods of sea fog will be possible out ahead of the next cold front expected to push through the region early Wednesday. Light to moderate offshore winds will prevail behind this front. This offshore flow will not last for long though, as moderate onshore winds will return Thursday. Towards the end of the week, the next frontal passage is expected to reach our bays and coastal waters on Friday afternoon. Moderate to strong offshore flow is anticipated behind this front, resulting in elevated wave heights between 3 to 5 feet. Hathaway && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 45 63 52 64 60 / 90 10 10 50 70 Houston (IAH) 48 67 57 69 63 / 90 10 30 60 60 Galveston (GLS) 56 63 60 67 64 / 80 20 40 70 40 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...Small Craft Advisory until midnight CST tonight for the following zones: Coastal waters from Freeport to the Matagorda Ship Channel out 20 NM...Coastal waters from High Island to Freeport out 20 NM...Waters from Freeport to the Matagorda Ship Channel from 20 to 60 NM...Waters from High Island to Freeport from 20 to 60 NM. Small Craft Advisory until 10 PM CST this evening for the following zones: Galveston Bay. && $$ Discussion...11
Hazardous Weather Outlook
Hazardous Weather Outlook National Weather Service Houston/Galveston TX 750 AM CST Sat Dec 16 2017 TXZ200-213-214-235>238-171400- Brazoria-Chambers-Galveston-Harris-Jackson-Liberty-Matagorda- 750 AM CST Sat Dec 16 2017 This hazardous weather outlook is for portions of Southeast Texas.. .DAY ONE...Today and Tonight A storm system will move across the area late this afternoon and tonight. On average, expect between 0.5 and 1.5 inches of rain. Localized higher amounts are possible where any training heavier cells occur. We will be monitoring the potential for isolated severe storms, more specifically the threat of tornadoes, between 5 pm and 1 am. This will dependent on the eventual track of a low pressure area moving up the coast. With warmer air spreading over the cooler nearshore waters, areas of sea fog may become an intermittent problem, outside of precipitation. .DAYS TWO THROUGH SEVEN...Sunday through Friday Unsettled weather, including periods of rain and sea fog, is possible Sunday night into midweek. A much colder airmass is expected to arrive late next week. We will be monitoring temperatures and precipitation chances a time gets closer. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed tonight. $$
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