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Disease risks from yesterday's rain

Winchester area received isolated rain events yesterday (6/5/10).  The intensity of the rain varied by area, thus, I'm just giving a general idea.  Based on the record, we had rains between 1-3PM and 7-10PM; however, the events were composed of a series of very light rains (less than 0.01 inches), the relative humidity was low (70-80% range), and temperature was high (mid-80's to mid-70's).  Thus, even though we could have a chance of a long wetness period, my guess is that leaves were not wet long enough for many fungal pathogens (Phomopsis, black rot, and downy mildew) to take advantage.  On the other hand, this humid hot cloudy condition may be ideal for powdery mildew development. 

We are still having a chance of rain this afternoon.  It seems like northern VA will receive some thunderstorms.
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Disease risks from yesterday's rain

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