Northwest Houston, TX, during the early morning.
Northwest Houston, TX, during the late evening.
Dense Fog Advisory for the Houston, TX area, issued by NOAA during the late night.
Locations: Northwest Houston, TX.
Thoughts: The day stayed cloudy to mostly cloudy. There may have been some light showers in the Houston, TX area, during the late night. It felt a little cool during the late morning and afternoon, and early night. I think it felt cool, during the early and mid-morning and late night.
Area Forecast Discussion
Issued by NWS Houston/Galveston, TX
Issued by NWS Houston/Galveston, TX
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000 FXUS64 KHGX 060300 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 900 PM CST Mon Feb 5 2018 .UPDATE... A cool and dreary night with lowering clouds...light precipitation ..and areas of fog development. A near-coastal warm front will work its way northward and into the southern 2/3rds of the forecast area through tomorrow afternoon. Cool easterly near surface flow along and behind this front...with mid-level westerly flow atop the frontal zone creating a steep overnight inversion...will trap low level moisture and make for continued raw conditions. Gentle upglide drizzle or periods of light rain/showers along and ahead of the warm front. Warm and moist air moving over cooler shelf waters will produce early evening marine fog and to subsequently advect inland...locally dense fog with visibilites falling to below and mile at times through late Tuesday morning. Many interior counties can expect low ceilings and patchy fog with intermittent light precipitation north of the warm frontal boundary. Model progs indicate enough instability (near 1k J/kg MU CAPE) with 6 to 7 deg C mid-level lapse rates to promote a mention of elevated PM thunderstorms. A cooler surface per easterly flow and overcast will really thwart any surface-based storms. A near 12k freezing level/10k wet bulb zero height suggests that..."if" efficient wet bulbing to saturation does occur within the hail growth zone...then (far interior county) small hail can be expected to fall out of any isolated strong afternoon thunderstorm. 31 && .PREV DISCUSSION... /ISSUED 525 PM CST Mon Feb 5 2018/ AVIATION... Warm front will be approaching the coast and moving inland tonight and Tuesday. Expect the typical unfavorable flying conditions that typically occur in these scenarios. MVFR conditions will transition to IFR & LIFR as low ceilings, fog, drizzle, -ra develop and persist across the region. Little improvement is expected Tuesday. 47 && PREV DISCUSSION... /ISSUED 354 PM CST Mon Feb 5 2018/ A relatively active week continues as yesterday`s cold front pushes back north through the area as a warm front, bringing back moisture and fog potential. Another cold front pushes through the area late Tuesday night into Wednesday morning, along with showers and thunderstorms - hail is a possible threat in the strongest storms Tuesday night, particularly for points from College Station and Huntsville northward. Spots well north of Houston look to fall into the middle 30s Wednesday night/Thursday morning, but thinking that with clouds only partially breaking behind the front, freezing temperatures aren`t a significant danger. Another front awaits us this weekend, and though details continue to be difficult to nail down, another shot of rain looks likely. NEAR TERM [Through Tonight]... Outside of a brief period this morning where the northern/eastern chunks of the area broke into sun, cloudiness has been the rule across Southeast Texas. So although a warm front is moving north across the area, these clouds have largely kept temperatures in check. Tonight, look for boundary layer moisture to continue to pump up with light onshore winds on the warm side of the front. This will bring a return for fog potential - first over the nearshore waters, but gradually become possible inland, as well. Where winds go calm, some dense fog should be possible, but where winds stay up, mixing should limit the density. Additionally, vertical motion along with increasing rain chances towards morning will also inhibit fog formation to some extent. Actually kind of like the HRRR`s general idea of greatly varying visibilities across the area. Of course, given the lack of skill in pinpointing such localized spots of denser fog, will hold at patchy for most, only going to areas for sea fog. SHORT TERM [Tuesday Through Wednesday Night]... The potential for warm sector showers will slowly nudge upwards through the day Tuesday as the cold front approaches from the north. Guidance suggests a thunderstorm may be possible with modest instability developing into the afternoon. Southwest winds at 850 may provide some capping to diminish that potential, but those winds aren`t terribly veered, so it may be a beatable cap. The Euro does hint at this with a couple convective-looking, if not terribly impressive QPF bullseyes Tuesday afternoon. Given continued cloudiness expected and our relatively lackluster heating in similar situations the past couple days, have gone ahead and taken a whack at highs tomorrow already. Meanwhile, at the immediate coast, sea fog may continue to encroach on the shoreline a bit. Things start to look a little more impressive Tuesday night, particularly late Tuesday night as the surface front reaches our area. Despite the loss of sun, we still hang onto a bit of surface-based CAPE at the coast, and forecast soundings suggest more elevated CAPE farther inland above the more stable nocturnal boundary layer with MUCAPEs in excess of 1000 j/kg. Deep layer shear is sufficient enough to support some organized updrafts, as well. It`s not a terribly fat instability profile, but the -20C point is near the maximum area of that CAPE trace, and for what it`s worth, SHIP is just shy of 1.0, which is near the 75th percentile for hail up to 1.5 inches. On the other hand, height falls are relatively negligible (even suggested height rises at one point?), the upper jet alignment is awkward, and low level convergence is relatively weak in our area with the 850 front focused well to the northwest. All in all, I wouldn`t go looking for quarters and ping pongs to start dropping from the sky, but the strongest storms will certainly have an environment in which they could produce hail, and a marginally good one for reaching that 1 inch severe threshold from points around College Station and Huntsville northward. The front shoves through the area Wednesday, most likely entering from the north in the pre-dawn hours, and reaching the coast around mid-day or in the early afternoon. This timing on the front means our diurnal temperature range is likely to to be nigh on nil, and we may even see temperatures slowly fall through the afternoon. The 850 front looks to lag behind, which sets us up for continued elevated thunderstorm potential. But with a slightly higher wet bulb zero, we may lose the top end potential for severe hail as convection marches coastward. Still, the strongest storms seem capable of producing some small hail, and as colder air aloft starts to move in for the late afternoon and evening, the SHIP numbers at IAH start to buck up again. WBZ is still a little high and there may be some question as to whether any storms will be present at all, so I`d still put the best chance for severe hail for the north on Tuesday night. But...it`s not impossible (cue SoYoureSayingTheresAChance.gif ). LONG TERM [Thursday Through Monday]... Temperatures will fall through Wednesday night as colder air moves in, and by early Thursday morning, some spots way up north (thinking near and north of Crockett) may dip into the middle 30s. How far we fall up there will depend on just how much clearing we see. Have been pretty pessimistic with the breaking of clouds, and so am thinking that will keep freezing temps out of reach. Also, this push of cold air isn`t terribly strong - with the lack of rain and some breaks in the clouds allowing filtered sunlight, highs on Thursday look to match and up north, even exceed Wednesday`s highs. The NAM suggests a few showers may linger into Thursday, but have not really bought into that yet, and it appears drier than when the previous shift noted the potential. So will follow suit with them and keep PoPs relatively low, but feel more confident in keeping clouds around, as winds just aloft to the mid-levels become more onshore, and set up potential isentropic lift. The focus then turns to the weekend and the next front. Starting to get a little jealous of the midnight shift, which always briefs me on relatively good agreement among the long range models. Then I get the 12Z set, and the GFS decides to do something wonky. Today, it tries twice to bring a front into our area and fails, not succeeding until the end of NEXT week. The Euro has stayed more consistent, albeit a bit slower, bringing a front through Sunday morning/mid-day. As far as this forecast goes, I suppose the impact on sensible weather remains relatively stable. Both models generate a subtle coastal trough, and that`s enough to produce rains in the warm sector ahead of the cold front far to our northwest. Some shortwaves in the mid-level pattern and the approach of a southern stream jet streak eventually putting us under the left exit region should support upward motion. With the GFS progging precipitable water at or above 1.5 inches, we may want to keep an eye out on precip potential. Indeed, for whatever reason, the GFS has come into line with the GEFS, and the ensemble`s envelope has become more moist itself. But, with another front to go before this one and the GFS showing so little run to run continuity, will not deign to speculate much on this right now. Luchs MARINE... Fog could develop and become widespread/dense late this afternoon through tonight and then persist until a strong cold front moves through the area on Wednesday. Moderate to strong north winds and rough seas are expected to develop in the wake of the front Wednesday through Wednesday night, and small craft advisories will likely be needed. Light to moderate east to southeast winds return to the area at the end of the week as surface high pressure moves off to the east. South winds Saturday and Saturday night can be expected until the next cold front`s arrival on Sunday. 42 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 53 65 47 47 38 / 30 60 70 60 10 Houston (IAH) 56 70 56 56 42 / 30 50 70 80 30 Galveston (GLS) 57 68 58 58 46 / 20 50 40 80 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...Dense Fog Advisory until 10 AM CST Tuesday for the following zones: Coastal waters from Freeport to the Matagorda Ship Channel out 20 NM. && $$ Discussion...31
Hazardous Weather Outlook
Hazardous Weather Outlook National Weather Service Houston/Galveston TX 358 PM CST Mon Feb 5 2018 TXZ163-164-176>179-195>200-210>213-226-227-062200- Austin-Brazos-Burleson-Colorado-Fort Bend-Grimes-Harris-Houston- Liberty-Madison-Montgomery-Polk-San Jacinto-Trinity-Walker-Waller- Washington-Wharton- 358 PM CST Mon Feb 5 2018 This hazardous weather outlook is for portions of Southeast Texas.. .DAY ONE...This Afternoon and Tonight A warm front will approach the area tonight. Areas of fog will develop and could become locally dense reducing visibility to less than a mile at times. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday A warm front will move through the region early Tuesday. Scattered showers and thunderstorms will develop Tuesday afternoon and a few of the stronger storms could produce small hail. A cold front will trigger more storms on Wednesday and a few of the stronger storms could again produce small hail. There is a marginal risk for larger hail on Tuesday night near and north of a line from College Station to Huntsville. A potent storm system will approach the area Friday night and Saturday. This system has the potential to produce locally heavy rain Saturday morning. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed. $$
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