Fireblight infection conditions - MaryBlyt model logic

Background Information for this page
Return to radar list for Greenville RI
Weather data for Greenville RI.  Forecast values begin August 3, 2008
Shoots near overwintered fireblight cankers would start showing obvious symptoms around  Tuesday, June 10
 If canker blight infection spreads to other shoots,
symptoms on those shoots would become obvious around Friday, June 20
   If fire blight blossom infection occurred on June 1, then blossom blight would be noticeable by June 10, and shoot blight by June 17.
Range of potential
open-blossom dates
Gray box indicates dates when most trees will have lost open blossoms and susceptibility to blossom infection, but late blooming cultivars or young trees may still be susceptible.
Inches Rain,
Leaf Wet Hours,
DH65 heat units, &
Avg. Temperature
Daily fireblight risk rating
as per Maryblyt model criteria
by Dr. Paul Steiner and Gary Lightner. 

In absence of rain, 3 or more hours of leaf wetness counted as possible dew conditions for adequate wetting, which may overstate risk on such days.
Infection requirements:
Any rain, or >0.1 inch rain on previous day,
+ 198 cumulative degree hours > 65F,
+ Average temp. on wetting day >= 60F
Mac King Bloom
Mon, May 5 
  0.'',  10 hrs.,  0 DH,  53F No FB infection
Tue, May 6    0.'',  0 hrs.,  26 DH,  58F No FB infection
Wed, May 7    0.'',  0 hrs.,  54 DH,  61F No FB infection
Thu, May 8    0.13'',  12 hrs.,  87 DH,  62F No FB infection
Fri, May 9    0.38'',  16 hrs.,  58 DH,  50F No FB infection
Sat, May 10    0.'',  9 hrs.,  44 DH,  51F No FB infection
Sun, May 11    0.'',  0 hrs.,  0 DH,  51F No FB infection
Mon, May 12    0.'',  0 hrs.,  0 DH,  47F No FB infection
Tue, May 13    0.'',  0 hrs.,  3 DH,  55F No FB infection
Wed, May 14    0.'',  0 hrs.,  6 DH,  55F No FB infection
Thu, May 15    0.'',  0 hrs.,  6 DH,  56F No FB infection
Fri, May 16    0.41'',  10 hrs.,  4 DH,  53F No FB infection
Sat, May 17    0.44'',  10 hrs.,  31 DH,  58F No FB infection
Sun, May 18    0.05'',  8 hrs.,  33 DH,  58F No FB infection
Mon, May 19    0.'',  7 hrs.,  22 DH,  52F No FB infection
Tue, May 20    0.28'',  8 hrs.,  17 DH,  52F No FB infection
Wed, May 21    0.'',  9 hrs.,  17 DH,  56F No FB infection
Thu, May 22    0.03'',  7 hrs.,  11 DH,  51F No FB infection
Fri, May 23    0.'',  0 hrs.,  13 DH,  57F No FB infection
Sat, May 24    0.'',  0 hrs.,  17 DH,  59F No FB infection
Sun, May 25    0.'',  0 hrs.,  66 DH,  60F No FB infection
Mon, May 26    0.'',  0 hrs.,  132 DH,  64F No FB infection
Tue, May 27    0.17'',  14 hrs.,  183 DH,  66F No FB infection
Wed, May 28    0.'',  3 hrs.,  176 DH,  56F No FB infection
Thu, May 29    0.'',  0 hrs.,  184 DH,  60F No FB infection
Fri, May 30    0.'',  0 hrs.,  170 DH,  64F No FB infection
Sat, May 31    0.21'',  7 hrs.,  112 DH,  63F No FB infection
Sun, June 1    0.'',  10 hrs.,  209 DH,  67F INFECTION RISK
Mon, June 2    0.'',  0 hrs.,  231 DH,  65F No FB infection
Tue, June 3    0.'',  0 hrs.,  320 DH,  69F No FB infection
Wed, June 4    0.5'',  19 hrs.,  320 DH,  60F INFECTION RISK
Thu, June 5    0.03'',  24 hrs.,  149 DH,  58F No FB infection
Fri, June 6    0.38'',  24 hrs.,  112 DH,  57F No FB infection
Sat, June 7    0.'',  12 hrs.,  199 DH,  71F INFECTION RISK
Sun, June 8    0.'',  0 hrs.,  538 DH,  79F No FB infection
Mon, June 9    0.'',  0 hrs.,  913 DH,  81F No FB infection
Tue, June 10    0.'',  0 hrs.,  745 DH,  81F No FB infection
Wed, June 11    0.'',  0 hrs.,  987 DH,  75F No FB infection
Thu, June 12    0.'',  0 hrs.,  744 DH,  70F No FB infection