AWIS Frost Locations and Time of Frost Thur. Morning (5 PM, 4/3/13)

— Written By

AWIS FROST LOCATIONS FOR TOMORROW MORNING AND ESTIMATED TIMES

Out of 64 locations in NC that AWIS provides a detailed hourly forecast product, these 12 sites are “positive” for likely frost in the morning. Many more locations in Central Piedmont could experience temperatures low enough to do blossom damage, even if “white frost” is not evident. Locations like Burlington are not really that different than Roxboro, and if winds become calm, I would look for temperatures to plummet with DEWP (dewpoints) in the low 20s. That is one thing that has really “fooled” a lot of growers this year – just how rapidly the temperature will drop at any point in the night if winds subside. For areas with low dew points, the “drill” is to start up sprinkling before the wet bulb drops below 31 F, and the wet bulb will hit 31 F in Roxboro at around 3 am, and so that is when you would want to start sprinkling. Again, the air is too dry in Northern Central Piedmont counties to see “ice crystals” easily form, and so you have to start protection at 31 wet bulb (note the  AIR temp will be about 35 F when Wet Bulb is 31 in Roxboro at 3 am:      Roxboro 3 am wet bulb

Location NC Min 4/4 7am DEWP – 7am Winds – 6-7 am FROST HOUR
Boone 27 22 0 4am
Currituck 35 28 3 5am
Edenton 34 30 2 5am
Elizabeth City 32 29 7 5am
Greenville 32 27 3 5am
Kinston 37 33 5 5am
Lousiburg 32 26 6 5am
New Bern 34 30 7 6am
Rocky Mt 32 28 3 5am
Roxboro 30 23 2 5am
Sanford 34 31 3 4am
Smithfield 34 30 5 5am

The Smithfield situation is different that Roxboro – there you will likely see a white frost scenario as DEWP is around 30 F, and you can start sprinkling when you see first evidence of ice crystals forming on the ground, weeds, lay flat, or in row cover. Areas with DEWP in range of 27-33 can use “visual cues” of ice crystals forming for start up time. Locations with DEWP lower than 27, must start at wet bulb of 31 F, and in Roxboro this will occur at 3 am when air temp is 35, as I said earlier. PLEASE use these start times with extreme caution. We have had instances where we have been off by as much as 2-3 hours (last year we had a problem in Salisbury where AWIS said FROST at around 4am and it happened around 1:00 am).

Late Afternoon Update from AWIS

AWIS Weather Services, Inc.
North Carolina Frost/Freeze Forecast
Produced at  303 PM CDT on Wed Apr  3 2013

… Forecast for Tonight …

Northeast NC Coast
Currituck/Camden/Pasquotank/Tyrrell Counties

**** NEAR FREEZING COLD LOCATIONS  ****
****  SCATTERED FROST PROTECTED AREAS ****

Lowest Temperatures:      33 – 41
Elizabeth_City Min          33
Range Dewpoint Temps:     22 – 32
Range Wetbulb  Temps:     33 – 40
AVG Wind Direction/Speed:  NE  6     Periods of Calm
AVG Sky Condition:     Partly Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
46 – 53   41 – 48   38 – 46   48 – 55   52 – 59   52 – 59
——–

East Central/SE NC Coast
Carteret/Pamlico Counties
**** LITTLE IF ANY FROST ****

Lowest Temperatures:      39 – 41
Morehead_City Min           41
Range Dewpoint Temps:     27 – 35
Range Wetbulb  Temps:     33 – 41
AVG Wind Direction/Speed:  NE  7
AVG Sky Condition:     Mostly Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
51 – 53   45 – 47   39 – 44   49 – 51   53 – 55   56 – 59
——–

Southeast NC
NWS FORECAST ZONES 87-90,96-101
**** LITTLE IF ANY FROST DUE TO CLOUDS ****

Lowest Temperatures:      37 – 42
Elizabethtown Min           39
Range Dewpoint Temps:     20 – 37
Range Wetbulb  Temps:     34 – 43
AVG Wind Direction/Speed:  NE  8
AVG Sky Condition:         Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
44 – 52   40 – 46   39 – 45   48 – 52   52 – 56   53 – 58
——–

North-Central NC
Franklin County Area

**** FREEZE COLD LOCATIONS  ****
** PATCHY FROST PROTECTED AREAS **

Lowest Temperatures:      30 – 39
Louisburg Min               30
Durations at/below 32:     0 –  3
Range Dewpoint Temps:     19 – 24
Range Wetbulb  Temps:     27 – 36
AVG Wind Direction/Speed:  NE  5     Periods of Calm
AVG Sky Condition:     Partly Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
36 – 48   35 – 43   35 – 44   45 – 52   49 – 55   51 – 58
——–

North/Central NC
Alamance County Area

**** FREEZE COLD LOCATIONS  ****
**** LITTLE/NO FROST DUE TO DRY AIR ****

Lowest Temperatures:      32 – 39
Graham_AG Min               35
Durations at/below 32:     0 –  1
Range Dewpoint Temps:     17 – 24
Range Wetbulb  Temps:     29 – 36
AVG Wind Direction/Speed:  NE  5     Periods of Calm
AVG Sky Condition:     Partly Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
37 – 42   36 – 41   38 – 44   47 – 52   50 – 56   53 – 58
——–

South/Central NC
Richmond County Area
**** LITTLE IF ANY FROST DUE TO CLOUDS/WIND ****

Lowest Temperatures:      37 – 40
Ellerbe Min                 39
Range Dewpoint Temps:     20 – 28
Range Wetbulb  Temps:     34 – 40
AVG Wind Direction/Speed:  NE  8
AVG Sky Condition:     Mostly Cloudy

Extended Forecast: Range of Lowest Min Temperatures in the Above Zones
Min Temps Valid For Morning of Given Date (May NOT include ALL cold pockets)

04/05/13  04/06/13  04/07/13  04/08/13  04/09/13  04/10/13
——–  ——–  ——–  ——–  ——–  ——–
39 – 48   39 – 42   41 – 44   48 – 50   51 – 54   54 – 55
——–

For more detailed information visit www.awis.com or call 888-798-9955.
Copyright 2013 AWIS Weather Services, Inc. All rights reserved.

Dr. E. Barclay Poling
Professor Emeritus/Extension Strawberry Specialist
Department of Horticultural Science
Campus Box 7609, 162A Kilgore Hall
NC State University
Raleigh, NC 27695-7609
919-418-9687 (Cell)
919-515-2505 (Fax)
barclay_poling@ncsu.edu
https://strawberries.ces.ncsu.edu

Written By

Photo of Barclay Poling, N.C. Cooperative ExtensionDr. Barclay PolingFormer Professor and Extension Specialist, Strawberries and Muscadines (919) 515-5373 (Office) barclay_poling@ncsu.eduHorticultural Science - NC State University
Posted on Apr 3, 2013
Was the information on this page helpful? Yes check No close
Scannable QR Code to Access Electronic Version This page can also be accessed from: go.ncsu.edu/readext?209172