January: Calmer Pattern To End The Month

[TxJohn]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
533 PM CST MON JAN 6 2014

.DISCUSSION...
SEE 00Z AVIATION DISCUSSION.

&&

.AVIATION...
CIRRUS WILL CONTINUE TO STREAM OVER THE AREA THROUGH AT LEAST 06Z
WITH SOME THINNING AFTER 06Z. WINDS WILL DECOUPLE OVERNIGHT AND
BECOME EAST TO SOUTHEAST ON TUESDAY. SPEEDS WILL BEGIN TO INCREASE
TOWARD LATE AFTN. LOWER CLOUDS WILL DEVELOP BETWEEN 00-06Z WED.


Is this good news or bad news in regards to hitting that 19 degree mark in Houston?

[Andrew]

Dewpoint up to 6 in Houston..it was at 4 earlier and rose to 5 and now 6......

Dewpoints upstream are lower and will transition this way as we move through the night. Dewpoints won't matter too much tonight as we won't have enough time to get anywhere close to them. The main concern will be cloud cover. That will make the difference tonight.

[TxJohn]

Dewpoint up to 6 in Houston..it was at 4 earlier and rose to 5 and now 6......

Dewpoints upstream are lower and will transition this way as we move through the night. Dewpoints won't matter too much tonight as we won't have enough time to get anywhere close to them. The main concern will be cloud cover. That will make the difference tonight.

Oh okay thanks...I thought since there'll be so much cloud cover...with extremely low dewpoints we won't stay "warm" because of the clouds as the extremely low dewpoints will balance everything out...that's why I was watching the dewpoints lol. I guess not then.

[srainhoutx]

Update from Jeff:

Monday AM Lows:

College Station: 23

Huntsville: 23

BUSH IAH: 28

Richmon: 27

Katy: 25

Pearland: 30

Galveston: 32

Conroe: 25

Hobby Airport: 29

Tomball: 27

Victoria: 31

Palacios: 31

Austin Bergstrom: 23

Beaumont: 27

San Antonio: 31

 Lowest recorded: Muleshoe, TX: 3

Hard Freeze Warning is in effect for the entire region tonight. Clouds today have kept temperatures about 3-5 degrees lower than expected and very near freezing N of I-10 and below freezing N of HWY 105. Temperatures at 500pm are already 33 at BUSH IAH and freezing at Tomball and Katy. High temperature at College Station was only 30 today and 35 at BUSH IAH. As clouds clear tonight and with done dry dewpoints in the 0-10 range expected very cold conditions…could lower lows a couple of degrees…but will leave it alone as a slightly latter clearing of clouds could keep temperatures up 1-3 degrees. Think temps. below are still looking pretty good along with duration.

 Forecasted lows (Tuesday Morning):

N of HWY 105: 13-17

Conroe Area: 14-16

N of I-10: 17-21

N of US 59: 18-22

Inside Beltway 8: 24-27

N of a line from Victoria to Bay City to Pasadena: 22-28

Coastal beaches (including Galveston Is): 29-32

 
Temperatures will be at or below freezing for 14-18 hours and at or below 25 for up to 12 hours.

Tropical vegetation will take a beating along with citrus and any exposed outside pipes will freeze including sprinkler systems...especially undrained back flow preventers. Exterior wall pipes could freeze at these temperatures especially in older constructed homes and in areas that did not rise above freezing today which is pushing the duration below freezing now close to 20 hours already.

[Andrew]

Dewpoint up to 6 in Houston..it was at 4 earlier and rose to 5 and now 6......

Dewpoints upstream are lower and will transition this way as we move through the night. Dewpoints won't matter too much tonight as we won't have enough time to get anywhere close to them. The main concern will be cloud cover. That will make the difference tonight.

Oh okay thanks...I thought since there'll be so much cloud cover...with extremely low dewpoints we won't stay "warm" because of the clouds as the extremely low dewpoints will balance everything out...that's why I was watching the dewpoints lol. I guess not then.

Dewpoints are a representation of the moisture in the atmosphere and usually help to determine where the temperatures could fall. At this point a couple of degrees in the dewpoint won't make much of a difference but cloud cover will. The main thing to keep an eye on is the wind speed and cloud cover. If winds die down and clouds clear then radiative cooling could occur. At this time cloud cover could be an issue.

[Paul Robison]

who told me not to worry about this?! who told me this wouldn't happen? FYI, we're right back to where we started from in 2011!!!!

Texas under power conservation alert amid freezing temperatures

Posted on January 6, 2014 at 8:08 am by Emily Pickrell in Electricity, Weather



HOUSTON — The Electric Reliability Council of Texas canceled a power emergency alert issued early Monday when freezing temperatures pushed demand, but encouraged continuing conservation as another cold night looms.

“Cold weather will continue through tomorrow morning and we will continue to monitor conditions closely,” said Dan Woodfin, ERCOT director of system operations. “Consumers are encouraged to use electricity wisely, and a conservation alert remains in effect throughout the ERCOT region.”

The council operates most of the state’s grid.

A cold front pushed temperatures well below freezing overnight across Texas and sent Houston-area temperatures to a low of 28 degrees by 7 a.m. That spurred demand for electricity to rise to 55,486 megawatts in the following hour, about 11,700 megawatts short of last year’s peak demand, which occurred in August.

One megawatt is enough to power about 500 homes under normal conditions or about 200 homes under extreme conditions.

Winter planning: Grid planners say Texas has enough power for winter demand

Monday morning’s demand was high enough to trigger the grid’s highest alert level before rolling blackouts are needed. A second-level emergency alert occurs when power reserves fall below 1,750 megawatts. Under those conditions, ERCOT can bring online all available power plants and can start tapping neighboring power grids.

To ease demand on the grid Monday, ERCOT asked big industrial and commercial operators to temporarily reduce their power use. The agency also brought on all additional generation resources, Woodfin said.

Extreme temperatures

The National Weather Service forecasts a high temperature of 40 degrees in Houston Monday. But temperatures are expected to drop to the mid-20s Monday night.

A similar cold snap in February 2011 triggered the last round of rolling blackouts in Texas. Power distribution companies, such as CenterPoint in Houston and ONCOR in Dallas, were asked to use rolling blackouts to cut up to 4,000 megawatts of demand from the system. Those rolling blackouts were caused by a higher-than-expected surge in power use due to the cold weather, combined with up to 50 power generating units going offline unexpectedly.

Power market: Vote to require spare power on Texas grid spurs debate

There were several emergency alerts in 2011, most triggered by record summer temperatures.

Peak demand in 2013 came during the summer, when it hit 67,180 megawatts on Aug. 7, coming close to the all-time record of 68,305 megawatts on Aug. 3 during the scorching summer of 2011.

Rolling blackouts

In an email Monday morning, ERCOT said rotating outages, if needed, would primarily affect residential neighborhoods and small businesses. They typically do not include critical-need customers such as hospitals and nursing homes.

Rotating outages typically are limited to a 10- to 45-minute span, but some can be longer. These outages are a necessity when supplies of reserve power are exhausted. They help avoid a domino-effect that could create a region-wide outage, according to ERCOT.

Power-saving tips

In a statement, ERCOT listed some power conservation ideas:
•Keep your thermostat as low as is comfortable, preferably no higher than 68 degrees.
•Turn off and unplug non-essential lights and appliances.
•Avoid running large appliances such as washers, dryers and electric ovens during peak energy demand hours (6-9 a.m. and 4-8 p.m.).
•Close shades and blinds at night to reduce the amount of heat lost through windows.
•Businesses should minimize the use of electric lighting and electricity-consuming equipment as much as possible.
•Large consumers of electricity should consider shutting down or reducing non-essential production processes.

See more conservation tips below and at www.powertosavetexas.com.

[ticka1]

hey folks its cold! but warmer temps are on the way!!!!

[srainhoutx]

Rain and storm chances increasing Friday into Saturday with temps near 70. We need the rain after all these single digit dewpoints.

[cristina6871]

It's 30 at my house.......I agree with those that have said it's not truly fun if it's just dry and cold....would love a snow flurry or two. I know it's bone chilling cold, but I'm already getting worked up about the next one!

[jeff]

That's a lot of cirrus clouds streaming NE across Texas. Tonight may be overcast, making it not as cold as this morning.

Yea I agree. I don't see us completely clearing out. That flow from the pacific remains pretty active. Interesting to note both the GFS and NAM show clear conditions all night but I doubt this will be the case. With winds calming down and ridging almost directly overhead it should be interesting to see how temperatures compare to last night.

I dont think we will have much problem getting colder than this morning especially in and around Houston. The question is do we reach into the 10's N and W of Harris County. Ceilings are bouncing all around between clear and cloudy in the METAR obs so the clouds are way up there... and we tend to cool pretty well under high based cirrus. May save us 1-4 degrees over forecasted lows...but still a hard freeze and long duration freeze for most areas. At 800pm CLL is 27 and CXO is 26. Temp fall has been roughly just over a degree an hour since sunset with winds 5-7mph...with winds dropping off to 2-5mph overnight if the temp continued to fall 1 degree per hour that would give CLL a temperature around 17 around 600am and Conroe 16.

[jeff]

All obs sites are freezing across SE TX except Galveston, Bay City and Pearland at 800pm

[srainhoutx]

Temp is down to 27.3 here in NW Harris County. Wind is out of the N at 3. My pool anti freeze protection system is cycling ever 5-7 minutes now. We dropped below 32 at 5:20 PM up here when the wind was still gusting to 18.

[jeff]

Current temp trends are matching 12Z NAM and 18Z GFS guidance very closely. For IAH 18Z GFS has 03Z temp of 29 while 12Z NAM 03Z temp of 30. IAH is 30 as of 800pm. GFS shows 21 and NAM 19 overnight for IAH. Looks dead on at CLL also...although the models both show clear skies as I think was mentioned before...but again the actual temp trend versus the forecast is matching well.

[ronyan]

32.0F reached here in Lake Jackson @ 845 pm

[ticka1]

27 here now

[ronyan]

Clouds are starting to thin out under this high. 29.0F here and falling, already colder than last night.

[TxJohn]

NWS showing 28 degrees for Houston right now....
Anyone know if we're seeing a significant clearing?

[Andrew]

NWS showing 28 degrees for Houston right now....
Anyone know if we're seeing a significant clearing?

It does look like we are seeing some clearing, epecially in Central SE Texas. Clouds are decreasing in thickness.

http://www.ssd.noaa.gov/goes/east/sc/mflash-vis.html

[unome]

Cypress area is sitting in the mid-20s at 3:45, but teens are just to our NW

a story from chron.com's Fuel Fix log, rather ironic: http://fuelfix.com/blog/2014/01/06/unex ... cmpid=hpfc

Unexpected plant outages pushed Texas into winter power emergency
Posted on January 6, 2014 at 1:25 pm by Emily Pickrell

"insufficient winterization caused the two plants to shut down, likely due to frozen moisture in critical instrumentation lines"

[srainhoutx]

As of 5:00 AM my temperature is 19.3F in NW Harris County.