California Air Resources Board - Meteorology Section
Basinwide Ag-Burn Acreage Allocation - Sacramento Valley Air Basin

Date:  27-May-18 Local Time:  06:38 AM Meteorologist:  Mims
Ag Burn Decision Above 3000 ft:  Permissive Burn Day (Fair)    
A.M. Stability (°F) = -1 Wind Speed (mph)  = 15
500 millibar height (decameters) = 576 Average Rainfall (in) = 0.00
Meteorological (MET) Factor   = 0.95
Air Quality (AQ) Factor (Basinwide 00-06 PST Average PM2.5) = 6.9
Allocation Equation: = 8575
   
ARB REVISED Basinwide Allocation _________________________________________ = 2000
Revised Allocation _________________________________________ = 2000
District Yesterday's
24-Hr Avg
PM2.5
Yesterday's
PM2.5
(0-6 PST)
Reduction
Factor
Proration Final
Allocation
(Acres)
Avg PM2.5
(0-6 PST)
Conc Stn
Colusa 5 5 1 0.17 200 5 COL
Sutter 8 8 1 0.17 200 11 YUB
Butte 8 7 1 0.17 200 10 CIC-GRD
Yolo/Solano 4 3 1 0.15 200 6 DAV-WOO
Glenn 4 4 1 0.13 200 3 WLW
Sacramento 9 7 1 0.09 200 11 SAC
Yuba 8 8 1 0.07 200 11 YUB
Placer 2 3 1 0.05 200 8 ROS
Tehama 5 5 1 200 acres
unless reduced
by PM
200 4 RBL
Shasta - - 1 200 - AND
When any district's 0-6 am average PM2.5 is >= 27 ug/m increasing concentrations will result in a reduction
in allocation acres (e.g. 27-28 : 20%, 29-30 : 40%, 31-32 : 60%, 33-34 : 80%)
ARB Comments
Cautionary Comments:
*** Restricted Fields Day ***
Changes today as building high pressure keeps the well-advertised warmup going with gusty northerly wind. Relatively warm overnight temperatures will lead to mid to upper 80s this afternoon with gusts to 25mph expected. Dispersion should remain springtime good with the noted wind exception. Caution also for damp fields since we did get a few sprinkles again yesterday.

24hr Outlook
*** Permissive Burn or Restricted Fields Day ***
Other than wind strength, not much change tomorrow with the high pressure and warm temperatures remaining. The north wind pattern ends Tuesday as the next in the long line of troughs keeping us cool in May moves in. This system should return us back to our Goldilocks pattern, not to hot, not to cold through the weekend.
Mixing Height Discussion:
Valley: Mixing heights near 2,500 feet by afternoon.
Winds:
Valley: Northerly 10-20mph, gusting to 25mph.
Delta: Southwesterly 5-10 early, turning Northerly 5-15mph gusting to 20mph this afternoon.