San Antonio weather question (Austin, San Diego: tornado, subdivision, live)

[Tommi]

When will SA begin warming up?

What months would you consider the winter months? What are the avg. temps?

When is the heaviest rainfall?

Will I need a heavy winter coat (I currently live outside of Philadelphia)?

Will I need a sprinkler system for our home?

Thanks,
TLL

[AnthonySA]

The best way to describe the weather in San Antonio is saying that it's invariable and very difficult to pinpoint. My new favorite example is comparing January 2006 (Avg High 72, Avg Low 43) with January 2007 (Avg High 57, Avg Low 36). Also note that January 2007 was the coldest month since December 2000 and the coldest January since 1985, so weather this cold for this long is obviously not common at all.

It is also not impossible to see truly hot weather during the winter months with record highs of 90 have occured in both December 1955 and January 1971 and record highs of 100 in February 1986. As far as cold weather goes, below freezing temperatures occur on average a few times per year and have happened only during the months of January, February, March, April (once), October, November, and December.

Our average temperatures for the following months are as follows:
Courtesy: National Weather Service Austin/San Antonio.
Month High (Rec) Low (Rec) Precipitation (Rec)
January 62(89) 40(0) 1.70"(8.52")
February 66(100) 43(4) 1.90"(7.88")
March 74(100) 50(19) 1.60"(6.12")
April 80(101) 58(31) 2.60"(11.64")
May 86(103) 66(43) 4.20"(14.07")
June 92(107) 72(48) 3.60"(11.95")
July 95(106) 74(60) 1.90"(16.92")
August 95(108) 74(57) 2.50"(11.14")
September 90(111) 69(46) 3.20"(15.78")
October 82(99) 59(27) 3.20"(18.07")
November 71(94) 48(21) 2.10"(9.46")
December 64(90) 42(6) 1.70"(13.96")
PRECIPITATION
*Wettest Year: 1973 (50.28")
*Driest Yeat: 1917 (10.11")
*Average: 30.10"


During the winter, our primary weather makers are strong arctic cold fronts which sometimes interact with a southwesterly flow from the jet stream aloft creating overrunning situations (all day rains/drizzle -- and if it's cold enough, wintry precipitation). We normally aren't lucky enough to get any precipitation this time of year without the jet stream running overhead. Snowfall is rare, occuring only 30 times in the past 120 years.

During the spring and fall, we have a more varied weather forecast with weather resulting from different sources. This time of year we deal with cold fronts that create enough lift to generate strong to severe thunderstorms in association with strong centers of low pressure, cut-off lows which will sit over the area and dump heavy rain. We are at most flood prone the fall if we do not see any cold fronts push down into the area allowing the gulf temperatures to drop. When this happens, the first strong cold front to sit on top of us will funnel in enough moisture to create a deluge (as in October 1998, October 2004).

Summers in South Texas are very difficult to forecast. All levels of our atmosphere are very quiet since the Jet Stream is located well to our north and cold fronts never reach further south than North Texas. This means whatever forms over this area will sit over us for a very long time. Movement from storm systems during this time of year are almost always 100% dependent over the position of the ridge of High Pressure. For us to have a rainy summer, the ridge of High pressure has to be stationed well to our east across Alabama-Florida. When this happens, winds will come from the SE (from the Gulf) and allow for Sea Breeze storms (summer-time downpours generated from a contrast of cooler moist ocean air and hot inland air... kind of like a mini cool front) to develop. This too also is when we are at highest risk for tropical systems. There is no need to worry about much danger from Hurricanes since we are well inland to escape the worst of it (however, if a fast moving Category 3 hurricane makes landfall in the Corpus Christ area and moves NW, we would experience hurricane force winds here in town for a substantial period of time.) Our biggest tropical storm threat are tornadoes, proven by Hurricane Gilbert in 1988.

As far as severe weather goes in our area, we do not see much of it and definitely less severe than other portions of the state. However, severe storms are possible throughout the entire year. We are south of Tornado Alley (you would have to travel north of Austin to enter) because our atmosphere is less prone to the sharp air mass contrasts than up north. With this said however, we do get hail storms almost every year, but what you want to most watch out for are blinding downpours during afternoon storms.

[AnthonySA]

Our current weather situation right now is very dry. We have been in a drought since December 2004. Both in 2005 and 2006, we struggled to reach 20 inches of rain for the entire year and had a few months where we had under an inch of rain. In fact, we went on a streak of months of below normal precipitation from October 2004 - November 2006. The streak ended thanks to typical winter El Nino patterns. In fact, El Nino allowed us to enjoy the 10th rainest January on record with over 4 inches of rain. Unfortunately, as El Nino is weakening, so will our rain chances this time of year.


I hope this was helpful.

[irnag]

I have heard this rash of cold weather is due to the Al Gore effect. Evidently he has been going around the country in support of his film on Global Warming. So far many of the cities he hits experience the coldest weather of the season while he is there.

[hello13685]

Interesting, so following your logic, he was in San Antonio, right? I missed him. When was he here? Sweetie, San Antonio is not a significant enough dot on the map for Al Gore to honor us with a visit. (Karaoke night at Chacho's would not have been a good enough draw for him.) Also, what do you think his ulterior motive was for telling us our earth's climate patterns are shot? Wait, that question requires a level of abstract thinking...

[AnthonySA]

You can't pinpoint year to year temperatures on global warming. Global warming is something that happens over a long period of time and the changes in the climate are gradual, not overnight.
It is not unusual that during El Nino years we have cool, wet winters here in South Texas. January 2007 just followed the same typical El Nino pattern.

As far as whats happening up north, it is not at all unusual that temperatures hover in the single digits or below zero. You have not heard anything in the way of all-time record lows up there.

[AustinTraveler]

Not to rain on anyone's parade here but let's stay on topic. The original question is not a debate on global warming.

Thanks.

[hello13685]

I sincerely believe that WOAI's Jennifer Broome is the BEST meteorologist in the country (I know, you are shocked that I think something in SA is the best I've seen anywhere, but it's true in this one case). I just LOVE her. She disagreed with the National Weather Service on hurricane Rita's path, and was right. But I wonder why she didn't predict this cold winter for us. I'm a weather geek, and WAS paying attention, too. Anyway, Tommi, I have seldom needed a winter coat (maybe for one week per year in February), it rains evenly throughout the year I believe, and it will begin warming up after mid-February.

[MichelleSG]

Tommi if it helps I can give you a relative type grade of what San Antonio is like. I am from San Diego and have lived in San Francisco, St Louis, and Maryland (DC area). If, on a scale of 1-10, San Diego weather is a 1 one for weather extemes (not too hot in the summer and not to cold in the winter), Dc area would be about a 6 or 7, St. Louis a 7 or 8 then San Antonio would be a 2 or 3. Sometimes the summer gets pretty hot but the summers in Dc were worse and I thought summers in St Louis were even worse than that (personal opinion here!). Winters in San Antonio can get cold but only for 3 days or so then it levels out again, usually in the 50's. No snow unless you live was far north, and occasional ice that the city totally shuts down for. You'll only need your snow heavy coat for maybe 10 days out of the year, maybe a ew more if you walk your dog early in the morning. As far as a spinkler system they are darned expensive out here, or at least in the northwest section of the city. The ground is all rock bed like 1 inch below the surface. I prefer having a spinkler system in, the grass will not grow without water and there's little to none coming from the sky most of the year. You don't use spinklers during the summer, the grass goes dormant. In the summer there are lots of people who go outside late at night and water their grass by hand, not my thing. BTW, I live on less than 1/4 acre in a subdivision and my sprinler system cost $2500 (I got the Saturday special though and paid $1800), just insane. In San Diego the same system costs about $500 but the ground isn't rock bed.

[spursfan]

Originally Posted by MichelleSG

Tommi if it helps I can give you a relative type grade of what San Antonio is like. I am from San Diego and have lived in San Francisco, St Louis, and Maryland (DC area). If, on a scale of 1-10, San Diego weather is a 1 one for weather extemes (not too hot in the summer and not to cold in the winter), Dc area would be about a 6 or 7, St. Louis a 7 or 8 then San Antonio would be a 2 or 3. Sometimes the summer gets pretty hot but the summers in Dc were worse and I thought summers in St Louis were even worse than that (personal opinion here!). Winters in San Antonio can get cold but only for 3 days or so then it levels out again, usually in the 50's. No snow unless you live was far north, and occasional ice that the city totally shuts down for. You'll only need your snow heavy coat for maybe 10 days out of the year, maybe a ew more if you walk your dog early in the morning. As far as a spinkler system they are darned expensive out here, or at least in the northwest section of the city. The ground is all rock bed like 1 inch below the surface. I prefer having a spinkler system in, the grass will not grow without water and there's little to none coming from the sky most of the year. You don't use spinklers during the summer, the grass goes dormant. In the summer there are lots of people who go outside late at night and water their grass by hand, not my thing. BTW, I live on less than 1/4 acre in a subdivision and my sprinler system cost $2500 (I got the Saturday special though and paid $1800), just insane. In San Diego the same system costs about $500 but the ground isn't rock bed.

Grass will die in the summer if you dont water it. To me a sprinkler system is almost a necessity, but thats just my opinion. You can never rely on the rain here as its either feast or famine.