Sunday, December 27, 2009
Saturday, December 26, 2009
Dec. 24 25F
Dec. 25 21F
Dec. 26 20F
Dec. 27 20F
This morning's low (on 26th) of 20F is the coldest since Dec. 28 2008 - when the low was also 20F. Very chilly for the desert but much warmer than many experienced the last several days!
Thursday, December 24, 2009
Wednesday, December 23, 2009
Sunday, December 20, 2009
Shown above is an Eastern Pacific IR image from 1400 UTC Sunday morning. At the present time there is a long plume of tropical and subtropical moisture extending northward into the S/W that will be digging down the coast. Thus, there is a nice "pineapple" connection in place. However, the NAM does not pick this plume up as the S/W digs. Rather, the NAM indicates that westerly flow around the base of the trough will shunt the low-latitude moisture off to the east and into Mexico. This connection should be monitored closely the next two days, since it has the potential to bring a more significant precip event to the Southwest than the model currently is predicting.
Wednesday, December 09, 2009
Quite the wind event in the El Paso CWA today (Tuesday, December 8, 2009). Widespread damage in the Sacramento Mountains with 70 mph wind gusts at an APRS mesonet site in High Rolls, NM (elev ~6250) and 55 mph at a WxUnderground site in Cloudcroft, NM (elev 8850). Both were recorded before 9am and were the last obs reported before apparent power outages stopped the data flow. Lots of trees and powerlines down, some falling into homes.
The 12z RAOB from EPZ showed a strong inversion just above the mountaintop level of the Franklin Mountains which bisect the city of El Paso. Wind Gusts on the east (leeward) side of town topped out at 79 mph at an AWS site, which was well supported by 75 and 78 mph gusts at other mesonet stations. Wind blew down the signature canopy at Cohen Stadium (which looks eerily like Denver Int'l Airport), roofs blown off structures, debris breaking car windows, trees down, etc. Also, the Transmountain highway was shut down due to high winds blowing rocks into the road. Lots of residents reported a "tornado" despite just scattered flat Cu at 6000 feet. Interestingly, a plot of all the "mesonet" sites on the East Side shows one site reporting a SE wind much of the morning (everyone else was SW), before turning due West with that 79 mph gust, after which it remained SW. Don't really trust the siting of all these stations (combination of AWS Schoolnet, APRS, WxUnderground, etc), but the one site in question hasn't been noted to have wind direction issues in lighter winds. Can't help but wonder if a rotor or some sort of lee-side eddy wasn't at work here and may have aided in the damaging winds -- the worst damage was sort of clustered in the area of this cock-eyed wind ob.
A notoriously windy site at Aguirre Springs, NM, on the east slopes of the Organ Mountains near Las Cruces has a 97 mph recorded gust which destroyed a well-built hay barn. Widespread wind damage also occurred at White Sands Missle Range Main Base, 'de-roofing' the Police Station there, knocking out powerlines, injuring 2 people, and finally sending workers home early. WSMR's mesonet includes a station at San Augustin Pass (elev ~5700), through which US-70 links WSMR with Las Cruces. Peak Gust 116 mph. Hurricane force winds there are common in WSW high-wind events, but 100+ mph is still quite notable.
Tuesday, December 08, 2009
Very late post today.
Brief summary of various aspects of the overnight storm event.
Precipitation - at 7 am this morning about 75% of the Alert gauges in Pima County had measured precipitation in past 24 hours. Those that had not had rain were generally in the southern portions of eastern Pima County and most of those had light rainfall after 7 am. We had
0.24" in the gauge at 7 am here at house and had 0.02" more in the next hour or so. Heaviest rainfall report I noted at 7 am was 1.65" at CDO and Coronado (i.e. up on the northwest flanks of the Catalinas).
Snows were quite heavy at high elevations in the mountains and the photo above shows a bit of snow on higher peaks of the Catalinas at right side of photo.
However, the main aspect of the storm was the very strong wind gusts that swept across most of state - many areas in almost all parts of state had winds of 50 to 60 mph and max gusts were considerably higher. For example, the Gutherie RAWS station reported winds of 79 mph, Horse Camp Canyon had 73 mph, and the anemometer on the roof of the Atmo building on campus also had 73 mph. The only station that reported thunder was apparently Phoenix and the SPC storm reports map indicates a number of severe thunderstorm reports in Arizona last evening. This was a "sneaky" severe storm situation in that the severe winds were produced by the extreme synoptic pressure gradients and the thunderstorms were along for the ride!
The most interesting thing about the photo above is that there is considerable dust hanging in the air, even after widespread precipitation. This gives an erie cast to the photo and as the preciptation areas moved to the east they had a distinct brownish cast to them. Very strange morning reflecting the power of the windstorm.
The strong S/W that produced th overnight weather in Arizona has swept eastward very quickly and is now bringing a very major snow event to the Central Plains and upper Midwest, in addition to widespread blizzard conditions tonight as the low intensifies.
Saturday, December 05, 2009
Friday, December 04, 2009
It was quite cold here this morning - coldest of the winter so far with a low of 23F. I noticed a lot of readings down in the 20s this morning across southeast Arizona. The coldest I saw at lower elevations was 21F at Sasabe. This was 14th freeze this winter here at house and 7th day down in the 20s.
Snow photo above is from Mike Hardiman in El Paso. he has taken a lot of nice shots of the snowfall produced in the New Mexico and big bend borderlands by the storm earlier this week (see below) and these can be viewed at
Tuesday, December 01, 2009
Alpine, CA at 1270', 32.83N 116.81W and are Alpine 3W on the hourly roundups out of San Diego
We had an under-predicted storm here on Saturday. I got 0.70" at my house with pea-sized hail, and some places nearby had over an inch of rain, with 5 inches of snow at Mt. Laguna.
Nice start to the winter season--things are less flammable now (a prime concern at my house).
Monday, November 30, 2009
Sunday, November 29, 2009
Photo above shows early morning rainbow today, Sunday the 29th, to the northwest of the house.
The state Department of Public Safety began warning travelers Saturday morning to avoid Interstate 10 near Casa Grande until the dust settled. The wind slowed down by the afternoon, but Public Safety spokesman Harold Sanders said visibility along the interstate from mile post 190 to 216 remained poor.
Sanders says officers are investigating five separate collisions in the area that resulted from Saturday's dust storms, including the one involving the two fatalities. He did not have details on the other collisions.
Wednesday, November 18, 2009
Friday, November 13, 2009
Thursday, November 05, 2009
Friday, October 30, 2009
Thursday, October 29, 2009
Wednesday, October 28, 2009
View of the State Capital in Denver this morning (October 28, 2009) as the snow storm begins to ramp up in Colorado.
Here in southeast Arizona we had mostly dust and wind yesterday afternoon and during the night. Temperatures have been falling since around midnight. Very little precipitation except at higher elevations. The Pima County ALERT network data show that 8 of the mountain sites reported measurable rainfall. Amounts were light except at Davidson Canyon which reported 0.24" - the Carr RAWS station reported 0.21". So this event, which materialized much more quickly than the long range models had been forecasting 5 or so days ago, brings us wind and winter-like temperatures. Winds were mostly in the 30 to 45 mph range as the cold front swept through, but there were some reports of higher maximum gusts at the RAWS stations in southeast Arizona: Mt. Hopkins 50 mph, Horse Camp 53 mph, Chiricahua NM Headquarters 55 mph, and the highest I found this morning - Gutherie 60 mph. So, words for the day are "bundle up and keep warm."
Tuesday, October 27, 2009
Morning web cam shot of sky this morning as strong short wave digs southward toward Arizona. Interestingly, this morning has been the coldest here at the house of the Fall, with a low of 38F.
The first low temperature in the 30s this Fall has occurred about two weeks later than last year when it was 36F on the 12th and 29F on the 13th. The lows here have been very steady during the past week with readings of 42, 42, 42, 42, 41, 40 and 38. It appears that the low at TUS airport this morning was 49 or 50F.
Friday, October 23, 2009
Thursday, October 22, 2009
These streaks had not drifted into Mexico from US military bases and I was left wondering about their origins."
Tuesday, October 20, 2009
Monday, October 19, 2009
Precipitable water has been increasing slowly the past 24 to 48 hours as Hurricane Rick's influence has inched the boundary between dry continental air and the subtropical air in Mexico northward. Values have reached around an inch over southeast Arizona and may help fuel additional storms today - particularly if the warm layer of air above 500 mb cools as the strong S/W over the Pacific begins to move toward Arizona. Unfortunately, there is no morning upper-air sounding available from Tucson this morning. Regardless a slight bit of local weather to keep up our interest.
Sunday, October 18, 2009
Saturday, October 17, 2009
WTPZ65 KNHC 172208
HURRICANE RICK TROPICAL CYCLONE UPDATE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP202009
310 PM PDT SAT OCT 17 2009
...RICK BECOMES A CATEGORY FIVE HURRICANE...
SATELLITE IMAGERY INDICATES THAT RICK HAS BECOME A CATEGORY FIVE
HURRICANE ON THE SAFFIR-SIMPSON HURRICANE SCALE WITH MAXIMUM
SUSTAINED WINDS OF 160 MPH...260 KM/HR.
Thursday, October 15, 2009
Monday, October 12, 2009
Tropical Storm Patricia (see IR image from 12 UTC above) is located south of the tip of Baja and is moving slowly north-northwestward. The combined influences of Patricia and the negatively-tilted trough off California have produced a long fetch of southerly to south-southwesterly winds from the south end of Baja northward into southern Arizona. There is a strong gradient in precipitable water (see the PW time series at atmo home page), ranging from half an inch along the southern Arizona border to over 2 inches at Navajoa, Sonora. Strong morning convection is underway about half way up the Gulf of California, and a low-level cumulus field is moving northward into southern Arizona. So, there are some indications that the current moisture plume, below 500 mb, from the subtropics may affect southeastern Arizona. The morning NAM model runs indicate the deeper moisture will just clip the southeast corner of Arizona and impact mostly New Mexico; however, the NAM also forecasts a strong southerly flow at 850 mb from the GoC into southern Arizona persisting for next 24 to 36 hours. So, something to keep an eye on to the south.
Tuesday, October 06, 2009
Jason Criscio sent the above photo a bit after 4 pm yesterday, asking if the NWS was trying a new procedure to be sure the upper-air sonde was reading correctly. He said the balloon (top center) had been floating above the NWS roof for about 15 minutes. However, he reported that it was still there after 7 pm and that he had seen another balloon launched.
So, Jason's photo shows one of the dangers of launching upper-air balloons from an open, exposed tub on top of a cluttered roof. The instrument package apparently snagged on the top of the tracking system dome, requiring a second sonde launch. The strange and unique launch system used at TWC (Tucson) is documented in the first part of the 21 June 2007 post titled
"Comments on the NWS Radiosonde Replacement System (RRS)" at www.madweather.com
Friday, October 02, 2009
Thursday, October 01, 2009
Wednesday, September 30, 2009
Surface dewpoints and precipitable water have been increasing steadily for last day or so -
Tds into the low 50s out at Sells and Sasabe, and even at the airport, with PW amounts generally an inch or a bit more. The night brought some middle clouds and light breezes and increased moisture (note the hazy sky at sunrise in view above) - leading to a very mild low of 67F here at the house. The official low at the airport appears to have been 75F!
Looks like there may enough moisture for showers later today in at least far southeastern Arizona, as well as showers and thunderstorms with the S/W to the north. Unfortunately, the S/W in the westerlies and the subtropical disturbances to the south-southwest are a bit out of phase, or we would have been looking at a nice end of September precipitation event. Perhaps things will be in better sync by the weekend?
Tuesday, September 29, 2009
This morning a very large area of storms and disturbed weather continued from the south end of the GoC southward to 10 degrees North off the southwestern Mexican coast. There is now a very large circulation spinning away to the southwest of the end of Baja - very close examination of satellite loops indicates that there may well be two circulations embedded within the larger low pressure area. It is a very interesting situation and presumably the NHC will append some formal identification to the system(s) later this evening or tonight.
The issue of most immediate interest is how far north the push of subtropical moisture will come before the front from the northwest pushes through tomorrow. The satellite PW loops indicate that the moist subtropical air has now pushed up to about 30 degrees north - as indicated also per current Td readings of 79F at Guaymas (??) and 66F at Hermosillo. The models indicate that the moisture plume will push north mainly into New Mexico. However, with strong pressure falls to the north and the rapid northward progress of the moist air during the past 36 hours, it is possible that moisture could affect southeastern Arizona briefly tomorrow - it is an interesting situation worth watching.