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

Date:  13-Feb-11 Local Time:  09:05 AM Meteorologist:  Hanrahan
Ag Burn Decision Above 3000 ft:  Marginal Burn Day    
A.M. Stability (F) = 12 Wind Speed (mph)  = 7
500 millibar height (decameters) = 573 Average Rainfall (in) = 0
Meteorological (MET) Factor   = 0.4
Air Quality (AQ) Factor (Basinwide 00-06 PST Average PM2.5) = 20.4
Allocation Equation: = 3786
   
ARB REVISED Basinwide Allocation _________________________________________ = 2000
Revised Allocation _________________________________________ = 1600
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 - - 1 0.17 200 - COL
Sutter 23 21 1 0.17 200 6 YUB
Butte 28 32 1 0.17 200 23 CIC-GRD
Yolo/Solano 23 26 1 0.15 200 22 DAV-WOO
Glenn 19 19 1 0.13 200 18 WLW
Sacramento 26 23 1 0.09 200 19 SAC
Yuba 23 21 1 0.07 200 6 YUB
Placer 10 12 1 0.05 200 5 ROS
Tehama 30 37 0 200 acres
unless reduced
by PM
0 41 AND
Shasta 30 37 0 0 41 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:
***Permiaaive Burn Day***
High PM levels in some counties has led to a reduction in acerage. A passing trof in the Pacific Northwest has helped dispersal conditions slightly by weakening the upper level ridge. This is the beginning of a pattern shift for the forecast region.

24 Hour Outlook
***Permissive Burn***
A series oftrofs are forecast to pass through this week, bringing precip and cooler weather.
Mixing Height Discussion:
North Valley: Mixing heights to reach 3000 feet this afternoon.
South Valley:Mixing heights to reach 2000 feet this afternoon.
Winds:
North Valley: Morning winds are northwesterly reaching 10mph, shifting to easterly for the afternoon.
North Valley: Winds light and variable.
Delta: Winds are light and variable