August 2011- Hottest and almost driest august on record

September 6, 2011

It seemed like the refuge-closing rains on July 31st, coupled with some localized activity in early August, might usher in the long anticipated monsoon but while there was often sufficient moisture in the air it seemed reluctant to give it up in any kind of a wide-spread manner. Too often the big rain events came in areas that did not need such intense events. This was most noticeable in the burn scarred areas of the Las Conchas fire in the Jemez.

The Sevilleta did get a handful of fair size storms, but many of the events were merely in the <5 mm category. The long-term refuge wide averages for August is 44.8 mm (1.76"). This year rainfall across the refuge varied from 7.3 mm at Bronco Well to 43.3 mm at South Gate and averaged exactly 20.0 mm for the entire refuge. For the 3rd month in a row rain on the last day of the month gave the impression that things were better than they were for most of the month. This was particularly true of the west side of the refuge where 2 of the 4 stations had gotten less than 3.5 mm. This late rain pushed the average past the 19.5 mm average of 2009 which is the lowest total in Sevilleta's 23 year LTER history. Actually, there have been quite a few rather dry Augusts during the past 10 years including '10 (28.0 mm), '09 (19.5 mm), '07 (23.5 mm), '05 (24.7)and '03 (28.6).

While dry might have been our first concern, hot had to be right up there. August did not have lots of extremely hot days but rather temperatures remained continuously warmer than normal throughout the entire month with a few (5) days creeping up to pick off new daily records highs. There were 3 days that the temperature went over 100 F. The normal average high for August is 89 F. There was only 1 day with the Sevilleta average below that and only 3 days with average highs below 90 F. Consequently this easily came in as the warmest August on record for the Sevilleta in its LTER history.

    August Record Temperatures - High 39.4 (102.9 F), Low 5.0 (41.7 F)
    August '11 Record Temperatures - High 38.3 (100.9 F), Low 12.5 (51.6 F) F)

August Meteorological Summary

                         August      August '11        August '11
Variable             Long-term* Mean    Mean           Mean Range
-------------------------------------------------------------------
Mean Max Temp (C)         31.62         34.2          31.8 - 35.2
Mean Min Temp (C)         16.46         18.7          16.4 - 20.2
Mean Average Temp (C)     24.04         26.4          24.1 - 27.7 
Mean R.H.  (%)            47.4          39.8          37.7 - 43.5
Mean Vap Press. (mb)      12.73         12.40        11.65 - 13.08
Mean Max Wind (m/sec)      9.9          11.1           8.0 - 11.1
Mean Solar Rad. (kWh/m2)  6.65           6.85         6.53 - 7.24
Precip.(mm)               44.8          20.0           7.3 - 43.3
---------------------------------------------------------------------
*Long-term refers to all of the Sevilleta met stations for 1989-2010

Albuquerque - Sevilleta Comparison

It seemed like the lid was still on the airport rain gauge during August. There were quite a few loud and flashy storms that passed through the Albuquerque area with the airport often getting little or none. The 36.5 mm that hit my house came much closer to a normal August. In any case, the August total certainly surpassed the total for the previous 7 months. So both ABQ and the Sevilleta are less than 25% of expected year-to-date.

Albuquerque also broke all of the previous August temperature records.

                Loc     Precip          Normal       % of Normal
=====================================================================
August          ABQ      23.6 mm        41.9 mm           56 %
                SEV      20.0 mm        44.8 mm           45 %

Year to Date    ABQ      38.4 mm       158.4 mm           24 %
                SEV      38.2 mm       165.5 mm           23 %
====================================================================
Remember to check National Weather Service Monthly highlights at:

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

Water year Precipitation

August precipitation obviously did little to help the water year deficit that keeps accumulating. With only one month left in the water year the Sevilleta is at 40% of normal. We actually need to get 41 mm during September to keep this from being the driest water year in Sev LTER history.

                 Precipitation (mm)

                1989-2010
Month           Mean            2010-2011    
===========================================
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
Mar 11          15.7               0.6
Apr 11          12.5               0.2
May 11          13.8               0.2
Jun 11          16.5               3.4
Jul 11          44.8              32.9
Aug 11          44.8              20.0
==========================================
Total          215.1              86.8


Monsoons

Not one of the best... but not the worst... yet months are arbitrary units for precipitation record keeping. One month does not make a monsoon. For the first 3 months of the monsoon the Sev has gotten an average of 56 mm - just about half of the long-term normal of 106 mm. Most years there is at least one month that is larger than the 56 mm. However 2003 had only 50.5 mm for these 3 months and 2005 was actually less than that with only 23.5 mm -remember, the year with no monsoon.

Drought

No good news. The Palmer seems to indicate that the central Rio Grande Climate division has gotten back into a non-drought range but the U.S. Drought Monitor still has 89% of the state in Severe to Exceptional Drought status. The other thing that has changed is that the Drought Monitor is no longer predicting an easing of the drought in NM as it had been doing up through last month.

ENSO

Double-dip seems to be the phrase of the day. Sea surface temperature anomalies are headed down again toward the La Nina range. The Oceanic Nino Index is locked at 0.0 for the second month in a row while the Southern Oscillation Index (SOI) is still headed down toward neutral conditions. It still too early to say that a second La Nina is definitely in the offing even though some of the indicators and models point that way.

 

Notables from on and off the Sev

Greening did begin following the late July precipitation but lack of additional moisture squelched a real flush. This was particularly true in the Deep Well to 5 points areas. Some other areas on the east side of the Sev have shown moderate greening such as along the east road on Mckenzie flats and down in the Gibbs Farm to South Gate area. The west half of the refuge appears pretty desolate. This is Bronco Well for example.

We shouldn't really complain. Texas has us beaten for hot and for dry. Arizona has us beaten for hot. And speaking of complaining, we also can't complain about dust storms after watching haboob roll through the Phoenix area this summer.

Hurricanes

There were actually 7 named tropical storms during August. Only Hurricane Irene got many people's attention. It was the first hurricane of the 2011 Atlantic season. Even though it seemed like the Northeast had dodged a Katrina-type bullet it is often the flooding rather than the wind or surge that causes the most damage. Damages have not been tallied yet. There has not been a strong hurricane (category 3 or higher) landfall on the east coast since 2005.

September Forecast

Drier and warmer than normal seems to be the continuing refrain... and who is going to question that?

D.M.