30 September 2003 Downy Mildew Forecasts

 

***** Forecast Notes - 25 September *****
Trajectories are coming in slowly today. We regret the situations this month regarding the availability of trajectories for the forecasts. Air Resources Laboratory (a branch of NOAA who provides us with the trajectories) informs us that increased use of their services and recent computer problems have combined to produce an unusually large strain on their systems.


FORECAST SUMMARY
: Tuesday, September 30 :

***** Disease Update - 25 September ***** Our thanks to Margaret McGrath in New York.... who informs us of a downy mildew outbreak in Suffolk County, NY near the town of Riverhead (this is in the eastern half of Long Island). This outbreak, of questionable severity, occurred in a 25-acre field of pumpkin. Lesions appeared to be fairly new. A trajectory for this site will be combined with the forecast for the New Jersey site.

***** The Weather...... southern / eastern U.S. ***** High pressure out of Canada will govern the weather over most of the eastern and southern U.S. through mid-week. Sunny to partly cloudy skies.... cooler than normal temperatures.... and dry conditions are expected for most areas for the next several days. The exceptions.... the southern half of FL will have showery weather, due to a lingering stationary front (what's left of the front that came through the eastern U.S. this past weekend)..... Drizzle or light rain showers are possible in the Lakes and Northeast tonight and / or Wednesday. Showers are possible for parts of the Ohio Valley later today and tonight. A few showers may also occur along the western slopes of the Appalachians tonight. These events are due to a cold front moving through the eastern / southern U.S. over the next two days. For all other areas, the frontal passage will bring no precipitation but will reinforce the cool air already in place. Temperatures will be well below normal for most locations. Early-season frosts are possible in some areas this week, mainly in the Great Lakes, Ohio Valley, Appalachian Mountains, and Northeast.

 

***** The Forecasts *****

Long-range survivable transport and deposition are unlikely for all transport episodes on Tuesday and Wednesday. Favorable weather in the southern half of FL indicates Strongly Moderate to HIGH Risk for crops in that region. There is Moderate Risk for localized disease development for the sources in the upper mid-Atlantic and Northeast (NJ and NY).... near the source at Vincennes, IN and across far southern IN on Tuesday... and for western slopes of the southern Appalachian Mountains. Otherwise.... Low Risk for all other cucurbit crops in the eastern and southern U. S. Tuesday and Wednesday.

TK


Current Sources:

 

Previous Sources:

Charleston, SC


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This service is provided by the North Carolina State University departments of Plant Pathology and Marine, Earth, and Atmospheric Sciences.