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

Date:  22-Dec-14 Local Time:  07:24 AM Meteorologist:  Branz
Ag Burn Decision Above 3000 ft:  No Burn Day    
A.M. Stability (F) = 1 Wind Speed (mph)  = 8
500 millibar height (decameters) = 581 Average Rainfall (in) = 0.03
Meteorological (MET) Factor   = 0.7
Air Quality (AQ) Factor (Basinwide 00-06 PST Average PM2.5) = 8.3
Allocation Equation: = 7412
   
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 12 10 1 0.17 200 9 COL
Sutter 7 6 1 0.17 200 10 YUB
Butte 4 3 1 0.17 200 5 CIC-GRD
Yolo/Solano 9 16 1 0.15 200 9 DAV-WOO
Glenn 9 3 1 0.13 200 5 WLW
Sacramento 8 3 1 0.09 200 4 SAC
Yuba 7 6 1 0.07 200 10 YUB
Placer 8 5 1 0.05 200 11 ROS
Tehama 9 3 1 200 acres
unless reduced
by PM
200 5 WLW
Shasta 12 9 1 200 15 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:
*** Wet Day ***
High pressure will strengthen over the region today as winds turn northerly. Expect dry and mild conditions today after patchy morning fog burns off. The Wet Day declaration continues due to rainfall from the past few days. Dispersion should not be as favorable today as the past few days with the building ridge in place.

24 Hour + Outlook
*** Wet Day ***
The strong ridge will remain over the North State through at least Tuesday. Northerly winds will continue, although they will be more light and variable for Tuesday. Expect dense fog, strong inversions, and poor dispersion beneath this ridge. An inside-slider type system will brush the area on Wednesday, bringing a chance of precip to the northern half of the Valley and the higher terrain. This quick-moving system should be east of the area by Christmas Day.

Mixing Height Discussion:
Valley: Mixing heights will reach 1000-1500 feet after morning fog and low clouds burn off.
Winds:
Valley: North to northwesterly 7-11 mph.
Delta: North to northwesterly 8-12 mph.