February 2011- Record-breaking cold temperatures across the Sevilleta and NM

March 3, 2011

Obviously the big story for February was the monster cold that invaded the state beginning on the 1st of February and hanging around for the rest of the week. Many places measured new all-time lows.

The Sevilleta, with only 22 years of records, saw its previous record low shattered. The Sev had new daily lows for 7 out of first 10 days of the month. Socorro saw a new record low (-14 F) while Albuquerque's 1971 record of -17 F was not touched by the -7 F recorded at the airport this year.

Besides record low temperatures there were also record highs, both real record high daily highs (two) but also record low daily highs. Before this year there had never been a daily high that was below 10 F, and only 3 days that every stayed below 15 F. On February 2nd none of the Sevilleta met stations got above 8 F; our Cerro Montoso station reached a high of only -1.2 F. Six of our 10 stations remained below 15 F on February 3rd.

This was the coldest average February in the Sev's 22 year history.  Average daily highs were warmer than 1994 and 2010,  but the average daily lows were far and away the coldest.  The average was about 1 degree F cooler than any previous February.

February Record Temperatures - High 26.5 (79.7 F), Low -21.8 (-7.2 F)
February '11 Record Temperatures - High 24.0 (75.2 F), Low -31.3 (-24.3 F)*
* New record for Feb and all-time

Quantification of moisture in February was problematic. Most of the moisture fell overnight from January 31st to February 1st. It came early as rain but quickly changed to snow as temperatures dropped. Some precipitation passed through the tipping bucket gauges, but some surely did not pass through before temperatures dropped below freezing. Strong winds for the next 2 days blew some or most of this snow back out of the gauges before the temperatures warmed up enough to allow melting on the 4th.

February Meteorological Summary

                       February       February '11      February '11
Variable             Long-term* Mean    Mean           Mean Range
-------------------------------------------------------------------
Mean Max Temp (C)         13.60         11.0           8.2 - 12.0
Mean Min Temp (C)         -2.57         -6.9         -31.3 - -26.1
Mean Average Temp (C)      5.51          2.1           0.8 - 3.3 
Mean R.H.  (%)            43.6          38.2          37.1 - 40.6
Mean Vap Press. (mb)       3.72          2.53         2.37 - 2.63
Mean Max Wind (m/sec)      9.8          10.7          10.1 - 11.4
Mean Solar Rad. (kWh/m2)   4.35          5.11         4.85 - 5.54
Precip.(mm)                9.0           0.8           0.0 - 2.9
---------------------------------------------------------------------
*Long-term refers to all of the Sevilleta met stations for 1989-2010

Albuquerque - Sevilleta Comparison

The early February storm dropped very little precipitation at the Albuquerque airport. This is often the case when there are strong east winds blowing through Tijeras Canyon. The mid and late month warming meant that Albuquerque came in with an average daily temperature of 37.0 F. This is 4.3 F degrees below normal and the coldest since 1973.

                Loc     Precip          Normal       % of Normal
=====================================================================
February        ABQ       1.0 mm        11.2 mm           11 %
                SEV       0.8 mm         9.0 mm            8 %

Year to Date    ABQ       2.8 mm        23.6 mm           12 %
                SEV       0.9 mm        17.4 mm            5 %
====================================================================
Remember to check National Weather Service Monthly highlights at:

http://www.srh.noaa.gov/abq/climate/Monthlyreports/February/2011/index.php

Water year Precipitation

The Sevilleta continues to fall further behind for the water year; it is now at only 44% of normal. This is the 3rd driest start to a water year in the 1989 to present record.

                1989-2010
Month           Mean            2009-2011    
===========================================
Oct 10          22.7              23.2       
Nov 10          13.3               0.4  
Dec 10          13.4               5.0
Jan 11           8.4               0.1
Feb 11           9.0               0.8
==========================================
Total           66.8              29.5

Drought

The drought conditions continue to expand in New Mexico. The U.S. Drought Monitor shows almost 2/3 of the state under drought conditions. However, the Palmer Drought Index does not indicate as grim a picture.

The hydrologic outlook does not look too good. Snow packs are generally at or below normal for northern NM. Rio Grand runoff is predicted to be 70 % of normal. This is with Elephant Butte at 37 % of average and only at 89 % of where it was last year at this time.

La Nina

There seems to be a decided weakening of La Nina. Biggest change seems to be seen in the Sea Surface temperature (SST) anomalies in the Nino1+Nino2 zone along the South American coast where anomalies have gone positive during the last month. Negative anomalies have declined in the other Nino zones as well. The Southern Oscillation Index (SOI) continues to remain very high at +2.7 and the 5-month running mean rose yet again to +2.18 which is the highest that it's been since back in 1974.

Notables from on and off the Sev

The effect of the cold temperatures on the creosote bush continues to be monitored. Even though the leaves remain green on the shrubs many of them are dead, have become brittle and fall off when squeezed. The extent of this dieback is still difficult to determine.

The loss of natural gas supply to several northern NM communities was certainly a painful experience for many. An index that is often used to show warmer or cooler than normal conditions is Heating Degree Days (HDD). This is the difference between the the day's average daily temperature (the average of the day's high temperature and the day's low temperature) and 65 degrees F. For Albuquerque, the average HDD for February is 28. For the 2nd and 3rd of February the HDD's were 60 and 59 respectively.  In northern New Mexico these numbers would have been much larger and even for the Sev at Deep Well these numbers were 65 and 73 respectively. The cumulative HDD for February for ABQ was 774 degree-days which is 104 HDD above normal. At the same time, the cumulative HDD for the season is 3130 which is 274 below normal.

A second blast of cold air that pushed New Mexico temperatures back down near or below zero the second week week of February ended up really blasting Oklahoma where temperatures hit the lowest ever recorded in that state. The temperatures rebounded extremely quickly so that in Bartlesville, OK temperatures went from -28 F to +82 F in 7 days - a 110 degree swing! The swing at our South gate station was from -24 F on the 3rd to 75 F on the 16th, only 99 degrees in 13 days.  There was a 77 mph wind gust at Albuquerque airport February 20.

March Forecast

NOAA says that there are higher chances of drier and warmer than normal weather for March. They have been wrong on temperatures for January and February.

D.M.