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Disease risks from yesterday's rain

Once again, it looks like Winchester area received a little less precipitations than other northern VA regions, but finally there were some moisture came to the ground.  On Thursday the 16th, we received short showers here and there, but the major event did not arrive until 10:30 PM when we received measurable rain, then the relative humidity was high until 9:00 AM on Friday the 17th.  Thus, it was 13.5 hours of estimated wetness hours with an average temperature of 65F.  Thus, it was Phomopsis, black rot, and downy mildew infection event.

I saw thunders, but we did not receive precipitation on Friday night; however, the relative humidity stayed high for a whole night.  That means that we had two consecutive nights with a high (>90%) relative humidity with temperature in mid-60's.  These warm nights are favored by downy mildew, and they tend to produce spores under these conditions.  Thus, the next rain event in the near future could be a high risk event for downy mildew.

Of course, I see some rain clouds coming toward our area on the radar.  I was hoping that I can spray this morning...  We will see...

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