30 Day Ag Weather Outlook VA – TN- NC – SC (7:45am, 12/22/14)
The overall forecast trend of generally mild temperatures will hold for the next week. High confidence that the upcoming week will see above average temperatures after a slightly cool start. Increasing confidence that a major weather pattern shift will occur in about a week as a significant push of cold arctic air moves into the East Coast with potential of major east coast storms in the last days of 2014 and into early 2015. We will need to keep a careful watch on the possibility of needing to re-apply row covers near the end of the year!
Fig. 1. Valid for Christmas day, 12/25/14. See Explanation about charts for more information about the chart’s three parameters: 1) sea level pressure (black lines), 2) 1000-500 mb thickness (blue and red dashed lines), and 3) quantitative precipitation (color shaded contours).
Forecast discussion day 3 – 5 (24 Dec – 26 Dec) Temperatures above seasonal average in east, dropping in west with precipitation early in the period. Temperatures start the period above average as a low pressure system is expected to move north out of the Gulf to the west of the region. This will bring mild temperatures with a large area of heavy rain and some snow in the western sections above 4000 feet early in the period. Late in the period, a cold front slowly moves through the area so temperatures drop to near normal in the eastern and drop to below average in the western parts of the region. The period starts off above the seasonal average with highs in the low 50s to low 60s and lows in the low 30s. Temperatures cool by late period with highs in the low 30s west and low 50s east, lows in the 20s west and 30s east. Precipitation expected to be in the 0.35” – 0.70″ range, with heavier amounts in the southern and eastern portions of the region.
Table 1. Climatology for 24 Dec – 26 Dec
Forecast discussion day 6 – 8: (27 Dec – 29 Dec) Temperatures go above normal to start period then fall dramatically late in the period. A low pressure system moves west of the region into Canada early in the period, followed by a strong high pressure system and cold surge by mid -period. Temperatures early in period expected to be above average with highs in the mid to upper 50s and lows in the 40s. Temperatures then expected to fall dramatically by mid period, first to slightly below average with highs in the mid-40s and lows in the 20s then to well below average with highs in the 20s – 30s and lows in the10s – 20s. Precipitation expected to be scattered and light early in the period in the 0.05” – 0.10” range.
Table 2. Climatology for 27 Dec – 29 Dec
Forecast discussion day 9 – 11: (30 Dec – 1 Jan) Temperatures below normal with possible major east coast storm mid period. Temperatures start well below average under a strong cold high pressure system. By mid period, a low pressure system is expected to move north out of the Gulf to the east coast with the potential of becoming a major east coastal storm bringing heavy rain and snow to the region. It must be emphasized that this is far enough out in the forecast that the details of the storm could change significantly, but this situation certainly bears close watching over the next week. The period starts off with temperatures well below average with highs in the 20s – 30s and lows in the10s – 20s. The temperatures warm slowly with the approach of the low, but still stay below average so that by mid period highs are in the 40s in the east but only in the 20s in the west. If the storm materializes, precipitation expected to be in the 0.50” – 1.0″ range, with rain in the coastal and southern portions of the region and snow in the western and higher elevations of the region.
Table 3. Climatology for 30 Dec – 1 Jan
Forecast discussion day 12 – 14: (2 Jan – 4 Jan) Temperatures drop well below average with artic surge of air. After the east coast low pressure system moves to the northeast of the region, a cold high pressure will push arctic air into region dropping temperatures well below average for the entire period. High temperatures are expected to range from 10s – 30s and lows in the 0s – 20s across the region early in the period. By mid period a low pressure system is expected to form in the Gulf and move northeastward and possibly become another major coastal storm. As the storm moves north it will bring slightly warmer air but still below average temperatures and heavy precipitation. If the coastal storms forms precipitation is expected to be in the 0.50” – 1.00” range.
Outlook discussion day 15 – 22: (5 Jan –12 Jan): Below average temperatures. Early indications are this period will remain active for east coast storm activity with below average temperatures for the season.
Outlook discussion day 23 – 30: (13 Jan – 20 Jan): Near average temperatures. Early indications are this period will see a moderation in temperatures to near average for the season.
NOTE: I will be posting my final 30 Day Ag Weather Outlook VA – TN- NC – SC of 2014 next Monday, Dec. 29. By then, I should have information about whether or not these strawberry weather (and production) advisories will continue to be offered on this website in 2015.
I wish you and your family peace and blessings for the Christmas season.
Dr. E. Barclay Poling
Raleigh, NC 27695-7609