As we enter the critical month of July, areas of the state may be exposed to episodes of climate extremes such as drought or heat waves. Eastern sections of the state have been dry, while many other areas have seen abundant rainfall restore depleted soil moisture reserves so far this season. Nevertheless July rainfall will be very critical for high yields to be achieved this year. Although the numerical forecast models are wide ranging for July rainfall, some showing shortages, while others suggest abundance, they all seem to agree that we will see spells of above normal temperatures that bring high Heat Index values. The Heat Index (HI) is driven both by temperature and humidity (dewpoint). When HI values exceed 105 degrees F it is a health risk to both humans and livestock. In addition such values generally amplify the stress on crops particularly if they are already moisture stressed.

Two new web products made available by the National Oceanic and Atmospheric Administration may be of value to crop advisors, farmers, and Extension Educators. The NOAA rainfall estimator is available at the following web site:

http://www.srh.noaa.gov/rfcshare/precip_analysis_new.php

These graphics allow for the spatial analysis of rainfall in real-time or going back to past storm events and episodes. Though not to be completely trusted for site-specific estimates of rainfall, they provide a good spatial description for each storm event.

In addition, NOAA produces a daily Heat Index forecast product that is useful in planning and preparing for heat waves. This information can be found at:

http://www.hpc.ncep.noaa.gov/heat_index.shtml

These forecasts are generally reliable and may help in anticipating periods of stress for both crops and livestock.

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