Fire Behavior Forecast

 

Forecast NO. 15

 

NAME OF FIRE: Bunnell Complex                       PREDICTION FOR: Friday Day Shift

UNIT: Bunnell                                                 __                   SHIFT DATE: June 19 1998

                                                                                                          SIGNED: Jim Brenner

                                                                                                                  Fire Behavior Analyst

TIME AND DATE

FORECAST ISSUED: 1800 EDT June 18,1998

 

WEATHER DISCUSSION: Partly cloudy, once again - high in the lower to mid 90's on the coast to the upper 90's inland. Expect temperatures to increase 5-6 degrees prior to the incoming sea breeze, this should only last less than one hour. Wind southwest 6-1 0 mph with a good possibility of a sea breeze about the same time as yesterday 1:30 - 2:00 pm. Today, the sea breezed moved in to St Augustine at 1:00 and Daytona at 2:00 reaching the Bunnell district office by 1:30. Yesterday’s humidities before and after the sea breeze.

 

Wednesday June 17,1998 -Daytona

Time of Day	Wind Speed and Direction	Temperature	Relative Humidity
1:00 PM	9 mph - West	97 degrees	41 %
2:00 PM	14 mph - Northeast	95 degrees	48 %
3:00 PM	14  mph - Northeast	96 degrees	42 %

 

Mixing heights are expected to move up to about 6,000 feet with a day time dispersion of between 55-60.

 

RELATIVE HUMIDITIES: Humidities will drop after sunup to between 40 and 42 % outside the sea breeze, at least 5 percent higher behind the sea breeze initially and then creeping up again until sundown.

 

20 FT WINDS: Winds will be between 5-6 mph with gusts higher in proximity to sea breeze front, and any 'wandering' Cumulus that might find their way into the area (higher probability - 20% especially

 

along the sea breeze front). Winds behind the sea breeze will be approximately 10 mph out of the east, and should extend further inland - 30 to 40 miles.

 

DISPERSION: Dispersions - after the upper level inversion breaks (8:30 - 9:00) will increase to between 55 and 60, mixing heights up to 6,000 by mid afternoon.

 

FIRE BEHAVIOR: Palmetto-Gallberry - Rates of spread predicted to be moderate (see attached) (2-3 mph) if fire is not knocked down by initial attack. Initial attack will require at least two tractors/units with a line building rate of at least 30+ chains per hour. Suppression efforts may be impacted by forecasted sea breeze in the afternoon.

 

Sand Pine Scrub - This fuel type does not have a standard model to forecast fire behavior, however, this fuel is most often associated with stand replacement bums (crown fires) and the rate of spread will be at least double that of the Palmetto-Gallberry, spotting distances will be mid to long distance, 0.25 - 0.5 miles. These fires are extremely dangerous, units need to workthe flanks and avoid the head if these fires are given any opportunity to build.. Failing trees as a result of the muck/duff burning out from under them will also present a significant hazard to fire fighters and to the line.

 

There is a better (20 + %) chance of isolated thunderstorms - in the event that a thunderstorm occurs near a fire be aware of wind gusts and wind direction changes resulting from thunderstorm outflow. Fire fighters should post lookouts for Cumulus buildup and remain on the side of the fire towards the thunderstorm, down drafts from the storm will push the fire out and away from the thunderstorm.