ABRFC Drought Briefing(04/12/2013)
......Significant Drought relief across the eastern half of basin.........
......Western areas still very dry.........
Significant drought improvement continues across much of the eastern half of the ABRFC, with several successive storm systems bringing beneficial rains to the region. Many locations have seen a 2-3 category inprovement on the US Drought Monitor during the past couple of months. Unfortunately, the beneficial precipitation has mostly missed much of the western areas of the basin, with extreme dryness continuing. Hopefully as we continue into a more climatologically wet period for the western areas, the beneficial rains seen in the east will transition westward.
Figure 1 shows the past 30 days of precipitation across the ABRFC area. The past 30 days brought 4"-8+" to many parts of eastern Oklahoma and western Arkansas, with more than 3" across much of the remainder of the eastern half of the ABRFC. Mostly light precipitation fell across the drought-stricken areas of The Panhandles, western Kansas, northeastern New Mexico, and southeastern Colorado. These areas continue to be significantly dry. More significant precipitation did fall in central Colorado, where a few late-season snowstorms brought close to an inch of liquid-equivalent to much of that area. Figure 2 shows the departure from normal precipitation across the ABRFC at the 30, 60, 90, and 180 day timescales.The 60 and 90-day periods show the contrast in precipitation across the basin nicely, with above normal precipitation dominating the east and below normal dominating the west. The 180-day image shows just how severe the drought was across the whole region during the 90-180 day period. Many areas of the western ABRFC received less than 50% of their normal precipitation during the past 6 months. That is a tremendous rainfall deficit, and indicates the seriousness of the drought situation. Figure 3 shows a six week animation of the drought designations from the U.S. Drought Monitor. This animation shows the continued drought conditions across much of the central U.S. that continue. Exceptional Drought (D4) is found across parts of the Oklahoma Panhandle, western Kansas, and eastern Colorado, as well as a small area near Wichita Falls, TX.. Extreme Drought (D3) surrounds the areas of D4, and covers a large part of the western reaches of the ABRFC. Significant improvements are seen in the animation during the past few weeks across the east, where drought conditions continue to improve. All drought designation was removed from parts of Arkansas, and that represents the first time in several months that the entire ABRFC wasn't in some kind of drought category.
Figure 4 shows the latest Drought Severity Index map based on the Long Term Palmer Index from the Climate Prediction Center (CPC). Significant to Extreme dryness is shown across much of the western reaches of the ABRFC. The CPC also generates the U.S. Seasonal Drought Outlook (Figure 5). Unfortunately, drought conditions are forecast to persist or worsen across the western areas of the basin through June 30. Improvement is forecast to continue in the east. The CPC's 3-month Precipitation Outlook is shown in Figure 6. The outlook calls for increased chances below normal precipitation across the southwestern parts ABRFC, especially New Mexico and West Texas, while the chances for above normal precipitation are increased in the northeast part of the basin. On the Arkansas River, most reservoirs in eastern Oklahoma are near or above their normal pool elevations due to the recent rainfall (Figure 7). A few reservoirs in the Red River Basin (Figure 8) still have significantly below normal pool elevations, although there is some improvement. Real-time river gage data from the USGS can be linked from Figure 9.
To view charts of the running precipitation total for 2013 compared to normal and for previous years back to 2006 for several locations across the ABRFC click here.
ABRFC is now producing experimental soil moisture graphics using parameters from our hydrologic distributed model. Click here.
Fig. 3: 6-week animation of previous Drought Monitor maps. Click here for direct link.
Fig. 4 CPC's Long-term Drought Severity Index. Click here for direct link.
Fig. 5: CPC Seasonal Drought Outlook. Click here for direct link.
Fig. 6: CPC 3-month Precipitation Outlook. Click here for direct link.
Fig. 9: Real-time USGS Streamflow Map. Click here for direct link.
|Main Link Categories:
River Forecasts, Observed Precip, Forecast Precip, Archive, General Info, Site Map, Contact Us