DROUGHT INDICATORS - September 1998

As of the end of August, New Mexico climate divisions 3 and 7 were in the Warning category. Division 3 had experienced a monthly average PDSI between -2 and -3 for two consecutive months, wile the monthly PDSI for Division 7 had been -2 and -3 for three consecutive months. Unless a widespread heavy rain event occurs before the end of September, Division 7 will be in the Emergency category by the end of the month.

Summer Precipitation: For the June through August period, the statewide average precipitation for New Mexico was 105 percent of normal. Generally, most of the area north and west of a line from Raton-Las Vegas-Ruidoso-Orogrande had normal to above normal summer precipitation. Most of the area south and east of that line had a dry summer. Lowest (relative to normal) summer precipitation was in the extreme east and southeast, where the worst drought conditions had already developed. Much of the area southeast of a line from Carlsbad to Clovis received less than 50 percent of the normal summer rainfall.

Reservoir and General Agriculture Conditions: Major reservoirs throughout New Mexico remain at 95 percent of the 15 year mean. Reservoir levels along the San Juan River and Rio Grande River decreased from last month, mainly due to heavy crop irrigation. The weekly Ag. Update is reporting similar drying conditions statewide. Soil moisture statewide is reported mostly short to very short. Crop conditions are in mostly good to fair condition with the exception of sorghum which is mostly in poor condition as a result of the dry summer in eastern New Mexico.

Weekly Trends of PDSI: The entire state of New Mexico is in a drying trend. By September 21 (using preliminary numbers), the weekly PDSI was below zero in all but two divisions (4 and 5). A four-week running average of -1.4 places Division 8 in the Advisory stage at this time.

Forecasts: The latest 13 month forecast from the Climate Prediction Center indicates the likelihood of below-normal precipitation and above-normal temperatures for New Mexico through the coming winter and spring 1999 seasons. This is based mainly on the development and intensification of La Nina conditions. This forecast is also consistent with the previous forecasts for the upcoming winter and spring.