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

Date:  16-May-21 Local Time:  07:34 AM Meteorologist:  Gerber
Ag Burn Decision Above 3000 ft:  Permissive Burn Day (Good)    
A.M. Stability (°F) = 3 Wind Speed (mph)  = 10
500 millibar height (decameters) = 567 Average Rainfall (in) = 0
Meteorological (MET) Factor   = 0.75
Air Quality (AQ) Factor (Basinwide 00-06 PST Average PM2.5) = 7.6
Allocation Equation: = 11709
   
ARB REVISED Basinwide Allocation _________________________________________ = 4000
Revised Allocation _________________________________________ = 4000
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 12 4 1 0.17 540 1 COL
Sutter 9 8 1 0.17 540 10 YUB
Butte 11 8 1 0.17 540 9 CIC-GRD
Yolo/Solano 9 8 1 0.15 500 9 DAV-WOO
Glenn 11 10 1 0.13 460 12 WLW
Sacramento 8 8 1 0.09 380 7 SAC
Yuba 9 8 1 0.07 340 10 YUB
Placer 11 12 1 0.05 300 11 ROS
Tehama 9 5 1 200 acres
unless reduced
by PM
200 6 RBL
Shasta 7 5 1 200 5 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:
*** Permissive Burn Day ***

Our unseasonably cold upper low will slowly push south and east this today. Still remaining some 5-10 degrees cooler than normal. Good onshore flow up the valley will help to keep dispersion good.

24hr Outlook
*** Permissive Burn ***
Weak ridging will move through behind the low for Monday, but a stronger trough to the north will push closer to the region by mid-week, enhancing onshore flow and keeping temperatures below normal into next weekend. Dispersion will be good through the week.
Mixing Height Discussion:
Valley: Mixing heights near 3,000 feet by afternoon.
Winds:
Valley: SW to SE 5-15 mph.
Delta: SW to W 10-20 mph.