January: Calmer Pattern To End The Month

[srainhoutx]

We have this thread that we started back in 2011 that has some good tips, txsnowman...http://forums.khou.com/viewtopic.php?f=2&t=549

Like Jason mentioned, I will wait until tomorrow before making some freeze preparations around my home. I will need to wrap some exposed pipes that are associated with my pool equipment and drain the lawn irrigation system if temperatures stay below 25 for more that 18 hours. I'm not sure we will get that cold for that long just yet. I believe by tomorrow we will 'see' just how cold this transient cold snap will last and how long or how many hours below freezing we may see. I survived February 2011 when temps stayed below freezing for 36 hours and dropped to a low of 14F with no problems. Those with pier and beam construction or older homes that were constructed before the mid to late 50's or mobile/modular homes where cold passes underneath the home -vs- concrete slab foundations may need to take some precautions. Thankfully this will not be a 100 hour+ freeze like we had in 1983 or 1989.

[txsnowmaker]

We have this thread that we started back in 2011 that has some good tips, txsnowman...http://forums.khou.com/viewtopic.php?f=2&t=549

Like Jason mentioned, I will wait until tomorrow before making some freeze preparations around my home. I will need to wrap some exposed pipes that are associated with my pool equipment and drain the lawn irrigation system if temperatures stay below 25 for more that 18 hours. I'm not sure we will get that cold for that long just yet. I believe by tomorrow we will 'see' just how cold this transient cold snap will last and how long or how many hours below freezing we may see. I survived February 2011 when temps stayed below freezing for 36 hours and dropped to a low of 14F with no problems. Those with pier and beam construction or older homes that were constructed before the mid to late 50's or mobile/modular homes where cold passes underneath the home -vs- concrete slab foundations may need to take some precautions. Thankfully this will not be a 100 hour+ freeze like we had in 1983 or 1989.

Great. Thanks as always, srainhoutx.

[srainhoutx]

NWS Houston/Galveston expecting the Arctic front to arrive Sunday morning and push off the Coast by mid day to early afternoon. They are forecasting 9-12 hours below freezing Sunday night and if winds can calm down as high pressure settles across the area Monday night, 12-15 hours below freezing may be expected. As far as temperatures are concerned for night ltime lows, Sunday night low to mid 20's mainly N of HWY 59 to near freezing along the Coast warming to near 40 on Monday and then dropping quickly Monday evening into the upper teens across our N and W as well as NE suburbs and the Piney Woods/Lake Livingston area with low to mid 20's in the Metro Houston and near 30 along the Coast including Galveston. Tuesday morning looks to be the coldest we have seen since February 2011 across our Region. Moderation is expected by Tuesday evening as winds return off the Gulf. We will likely need to monitor just how much snow falls across Oklahoma Saturday night as some possibly colder temps could occur if the snow is more widespread than expected N of the Red River Valley into Arkansas. There is a slight chance of some freezing rain/sleet across far NE Texas/Northern Louisiana as the Arctic front passes. For our neighbors in the New Orleans area and across Arcadia, freezing rain/sleet chances N of the Lake may be possible and a Hard Freeze is likely into the Delta early Tuesday. For Central Texas, Hard Freeze is expected with mid teens across the Hill Country Highlands. For the Corpus Christi area, Hard Freeze is likely N of HWY 35 and the Brush Country. Near freezing temps possible just N of Brownsville with freezing temps expected in McAllen/Harlingen. Wind Chill Advisories/Warnings may be hoisted for ALL areas Sunday night as gusty winds settle across Texas with a 1042mb Arctic High pressure cell with its origin from the Arctic/Siberia. Stay Tuned.

[redneckweather]

Good discussion srain. NWS is calling for a high of 43 right now on Monday in my neck of the woods (central Montgomery County). I believe those numbers will need to be trimmed back to mid to upper 30's under cold air advection from the arctic hp. As the sun sets above the pine trees temps will dip to the freezing mark pretty darn quick and stay that way till getting above freezing sometime mid to late morning on Tuesday.....then the warm up begins! The sooner the better. Not a big fan of nose bleed cold.

[srainhoutx]

I'm no fan of cold weather either, redneckweather. Maybe it's because I'm getting too old to enjoy it for long. My idea of enjoying cold weather is if we get something beside cold rain and endless cloudy days, but that's just me. I do enjoy the novelty of a Winter Weather event as long as it isn`t an ice storm. My idea of cold weather is hopping on an airplane and flying out W and enjoying the snow in the mountains where it belongs. Thanks for the kudos. The initial cold front is jus pushing into the Panhandle and as lee side cyclogenesis develops later today, or the surface low develops over New Mexico and begins its trek E across North Texas, those bitter cold temps currently diving S into Montana/Wyoming into the Northern Plains should accelerate quickly S on the back side of that surface low and arrive Monday.

The attachment 0042014 1330Z Surface Chart 90fwbg.gif is no longer available

The attachment 01042014 12Z 24 Hour Temp change t0.gif is no longer available

[srainhoutx]

Morning Update from Jeff:

Arctic cold front will bring very cold conditions to the region Sun-Tues…coldest air in 3 years is likely.

Preparations for a damaging hard freeze should be underway.

Arctic boundary is blasting down the plains this morning and will plow across TX tonight and off the coast early Sunday. High temperatures will occur prior to the frontal passage with a quick drop and continued fall of temperatures all day on Sunday even under mostly clear skies. Strong north winds of 25-30mph will drive wind chills into the 20’s and 30’s on Sunday.

Sunday night-Monday morning:

Damaging advective freeze is likely across much of the area along with gusty north winds and low wind chills. Large 1040mb arctic high building into TX will continue winds overnight and this would usually save the region from a freeze however this air mass is so cold that the freezing line will push south under the influence of the strong cold air advection. Expect temperatures to fall to freezing by mid evening north of HWY 105 and midnight north of US 59. Lows Monday morning will range from 24-27 north of HWY 105 to 26-30 along and N of US 59 to 31-35 along the coast. Gusty north winds will hamper the typical freeze precautions of covering tropical vegetation as this process does not work well with the wind blowing and removing the ground warmth away from the vegetation. These types of freezes tend to be damaging for vegetation for this area. Wind chills Monday morning will range from 15-22 across the region. Duration below freezing 6-10 hours.

Cold air advection will continue on Monday with highs only reaching the low to mid 40’s under sunny conditions and continued north winds.

Monday night-Tuesday Morning:

Large arctic high pressure dome will be nearly overhead with very low dewpoints (1’s to 10’s) over the region with clear skies and near calm winds. This supports an excellent setup for a hard radiative freeze across much of the area. One item that may keep the temperatures from really bottoming out is that the large high will be moving eastward during this time and may get just far enough east to allow a weak onshore wind flow to develop between 300am and 600am Tuesday morning…however this will likely not save the area from a hard freeze…but may keep areas out of the upper 10’s. Expected lows will range from 19-22 north of HWY 105, 21-26 along and N of US 59, and 28-32 along the coast. Interior coastal counties could be in the 26-29 range. Some of the latest model guidance is even colder than this for Tuesday morning with the GFS forecasting a low of 15 at Conroe….think this is a bit too cold at the moment…but will have to watch. Duration below freezing 12-16 hours.

Large arctic high moves eastward Tuesday allowing southerly winds to return and a fairly quick return of moisture. Dewpoints will rise into the 50’s by Thursday and with very cold nearshore temperatures may start to see sea fog and drizzle move inland from Wednesday afternoon into Friday.

[jeff]

12Z GFS has 13 for CXO Tues AM and 21 at IAH. 12Z NAM has 19 for IAH. Could see upper 10's into NW/N Harris County on Tuesday AM from Katy to Cypress to Humble.

[Texaspirate11]

13 DEGREES?????????????????

I surrender.

[jasons2k]

The forecast is very concerning for gardeners. The advective nature of Sunday night's freeze may be worse than 2011. I'm going to do what I can to save my last majesty palm (lights, wraps, etc.) but it may be futile with the wind. I am prepared to lose it along with my last pygmy date and plant something more hardy. I'm just tired of fighting it until I can retire, someday, to a warmer climate. All the tender plants - the ti plants, ginger, bird of paradise, cannas, etc. will have to start fresh in the spring for sure.

FYI: Any leftover citrus needs to be harvested now. Citrus trees will take a beating, esp. the tender varieties. Pygmy dates and anything more tender than those are at high risk, especially up north & west. This will be borderline for queen palms, especially up north. If the forecast goes any lower, they will be in trouble too. The eucalyptus trees planted along several freeways & interchanges will get leaf burn but should survive.

Canaries, sagos, and fan palms will be fine, but Mexican fans may get leaf burn.

Semi-tropical shrubs such as oleanders will burn back, depending on the variety/hardiness but should come back in the spring.

[srainhoutx]

Unfortunately, the 12Z Euro has trended colder as well. Freeze preparations completed around my home and fortunately we replaced most of our tropical plants with a more cold hearty Texas verity after the 2011 hard freeze.

[srainhoutx]

NWS Amarillo will expand their current Winter Weather Advisories to include most of the Panhandle. NWS Norman, OK may issue Winter Weather Advisories as trends noted across Colorado into Kansas suggest the guidance has under estimated the amount of snow and available moisture associated with the short wave diving S across the Front Range of the Rockies. Also higher snow totals expected for the Tulsa/NW Arkansas/SW Missouri Region where 2-4 inches of snow with isolated higher totals may be expected.

[Katdaddy]

I went ahead and wrapped the outside exterior pipes just in case down here in N Galveston County and brought in the only plant that would not survive.

[srainhoutx]

Worrisome to see a 1040mb Arctic high centered over the Hill Country at 00Z Monday night via the 00Z NAM/4km WRF. That would suggest winds going calm with ideal radiational cooling conditions with clear skies. Tuesday morning looks very cold across our Region. I will not be surprised to see Hard Freeze Warnings hoisted across most of SE Texas tomorrow.

[TxJohn]

Worrisome to see a 1040mb Arctic high centered over the Hill Country at 00Z Monday night via the 00Z NAM/4km WRF. That would suggest winds going calm with ideal radiational cooling conditions with clear skies. Tuesday morning looks very cold across our Region. I will not be surprised to see Hard Freeze Warnings hoisted across most of SE Texas tomorrow.

If that comes to fruition would that mean teens in the Houston area?

[TexasBreeze]

Hard freeze watch for all SE TX issued for Sunday nite and Monday morning.

[srainhoutx]

John, such conditions with the Ridge to our NW would suggest that College Station on down into Western/NW and N Harris County may well see temps in the mid to upper teens. Let's see what the other guidance suggest and if the guidance continues to under estimate the magnitude of this very cold air mass.

[Portastorm]

Interesting evening update from HGX:

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
903 PM CST SAT JAN 4 2014

.UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.

&&

.DISCUSSION...
THE ARCTIC COLD FRONT IS MAKING ITS WAY SOUTHWARDS THIS EVENING
AND PICKING UP SPEED AS IT APPROACHES THE DALLAS/ FORT WORTH AREA.
AT CURRENT SPEED THE FRONT IS PROGGED TO MAKE IT TO COLLEGE
STATION BY 5 AM AND CONTINUE TO ACCELERATE AS IT APPROACHES THE
COAST AROUND 11 AM. BECUASE OF THESE TRENDS HAVE UPDATED GRIDS TO
ACCOUNT FOR THIS FASTER MOVEMENT.

BEHIND THE FRONT THERE IS SOME VERY COLD AIR. GUIDANCE HAS
CONTINUED TO TREND DOWN. THE NAM AND GFS GUIDANCE BOTH SHOW
TEMPERATURES IN THE TEENS FOR OUR AREAS NORTH OF INTERESTATE 10
TUESDAY MORNING. THE GFS IS STILL THE MOST AGGRESSIVE WITH THE
COLD AIR. THE GFS GUIDANCE IS GOING 15 DEGREES IN SOME LOCATIONS
TUESDAY MORNING. EVEN MONDAY MORNING TEMPERATURES BELOW 25 DEGREES
LOOK LIKELY. BECAUSE OF THIS HAVE ISSUED A HARD FREEZE WATCH FOR
THE ENTIRE AREA STARTING SUNDAY NIGHT INTO MONDAY MORNING. THIS
WILL LIKELY NEED TO BE UPGRADED TO A HARD FREEZE WARNING THIS
MORNING OR TOMORROW AFTERNOON.

[TxJohn]

"GUIDANCE HAS
CONTINUED TO TREND DOWN. THE NAM AND GFS GUIDANCE BOTH SHOW
TEMPERATURES IN THE TEENS FOR OUR AREAS NORTH OF INTERESTATE 10
TUESDAY MORNING. THE GFS IS STILL THE MOST AGGRESSIVE WITH THE
COLD AIR. THE GFS GUIDANCE IS GOING 15 DEGREES IN SOME LOCATIONS
TUESDAY MORNING. EVEN MONDAY MORNING TEMPERATURES BELOW 25 DEGREES
LOOK LIKELY."


Too bad no moisture to work with...but interesting nonetheless.

[skidog40]

precip

[Andrew]

One thing to note is the differences in dewpoints between the GFS and NAM. The Gfs has dewpoints in the negatives for our northern counties while the NAM keeps dewpoints in the single digits. A good 10 degree difference between the two, which is a result of the placement of the ridge Monday night. The longer/slower the ridge progresses east will delay the onshore flow that will raise dewpoints and temps. Still a lot of timing details to be ironed out. I suspect we will see an outcome that is a mix of the two models. Either way both models show clear conditions and temps should bottom out. IF we stay clear (and that is always suspect), the models usually have a hard time accurately predicting the lows. Could see temps verify a couple of degrees colder than predicted if that is the case.