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Disease risks from today's rain

Most of northern VA did not see precipitation until very late last night (~1:30 am).  It seems that the storm system missed most of us, unless you are in West Virginia.  At Winchester location, a series of rain started around 1:20 am, then there were several precipitation intermittently, and it resulted in a total of 0.34 inches of rain.  The relatively humidity was stay high (>90%) until 10:00 am.  Thus, if you count the very first rain, we observed around 8.7 hours of wetness.  The average temperature during this event was around 73F.

This was a borderline event for black rot and Phomopsis because they requires about 8 hours at this temperature.  For downy mildew, the temperature range was optimal, thus, the infection risk was probably high.  Also, it was long enough for powdery mildew to discharge ascospores. 

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