Services Provided by the National Weather Service

Basic Services

Fire Weather Planning Forecast (FWF)

Product Overview and Issuance Criteria

The FWF provides a detailed prediction of elements for three specific 12-hour periods (four 12-hour periods with the afternoon forecast), a general 3 to 7 day forecast, and an 8 to 14 day extended outlook. The FWF is issued twice daily, once during the morning (between 3:00 and 6:30 AM), and the other during the afternoon (between 2:00 and 4:00 PM). The morning forecast, to be disseminated no later than 8:30 AM, consists of three periods: "Today" (valid from issuance through 6 PM local time), "Tonight" (6 PM to 6 AM), and "Tomorrow" (6 AM to 6 PM). The afternoon version , to be disseminated no later than 4:00 PM, consists of four periods: "Tonight" (6 PM to 6 AM), "Tomorrow" 6 AM to 6 PM), "Tomorrow Night" (6 PM to 6 AM), and the "Following Day" (6 AM to 6 PM).

Format/Content of the FWF

Note: The lowest average humidity typically occurs during the warmest part of the day. However, if it is expected to occur at a different time of the day, this will be noted in the "Remarks" portion of the forecast.

- Refers to a multiplication of the mixing height and transport wind., With units in ft MPH. Ventilation rates, forecasted during the daytime, are used to calculate the Burn Category for each day. The ventilation rate gives the potential for the atmosphere to to disperse smoke. Refer to Appendix 1 for further details regarding the correlation of the Ventilation Rate and Burn Category.

Note: Not included by WFO MRX.

- Refers to the forecasted smoke dispersion category at night, based on the surface wind speed. The dispersion category gives a general indication of the state of the atmosphere with respect to its ability to disperse smoke. The dispersion forecast (nighttime) is analogous to the daytime Ventilation Rate, though only a forecast during the evening hours is provided as a large majority of controlled/prescribed fire operations are completed before midnight. A spot forecast is recommended for critical operations that might involve smoke drift towards a populated area. Refer to Appendix 2 for further details on Dispersion categories.

Note: WFO's GSP and ILM do not produce surface wind based dispersion forecasts due to differences in categories between NC and SC.

WFO's AKQ, GSP, ILM, MHX, and MRX produce a Lavdas atmospheric dispersion index (ADI) forecast computed from the 20-foot wind speed, mixing height, transport wind, and cloud cover. The value reported is the average maximum value for the zone grouping, which filters out extremes. Refer to the Appendix for further details of the GSP and MRX Lavdas dispersion index (ADI). All WFO's except produce early and late period values of ADI both night and day, while WFO MRX produces one ADI value during the day.

- An index derived from the Lavdas ADI and the relative humidity, that gages the probability of visibility restrictions in fog or smoke. The index is based on a study of traffic accidents in Florida. The value reported is the maximumm value for the zone grouping, in order to capture the highest values. Refer to Appendix 2 for further details on LVORI categories.

Note: Included at WFO's AKQ, GSP, ILM, and MHX, early and late in each period, both night and day.

- The minimum surface visibility, and if restricted below 7 miles, the obstruciton causing the restriction. The value reported is the minimum value for the zone grouping, in order to capture the lowest values. Visibility values of 7 to 10 miles are considered unrestricted.

Note: Included at WFO GSP, early and late in the first two periods, both night and day.

- A numerical value, which is used to describe the expected lightning activity for that day. Refer to Appendix 3 for further details on the LAL.

- The index infers the stability of the atmosphere. In the North Carolina Coastal Plain and Piedmont, "low elevation" is assumed for the calculation of the Haines Index. It utilizes the atmospheric temperature at 950 mb and 850 Mb as well as taking into account the the moisture levels (dew point depression) at 850 Mb. In the North Carolina mountains, the "mid level" Haines Index is calculated using the temperatures at 850 Mb and 700 Mb, and the dew point depression at 850 Mb.

Haines Index values range from 2 through 6.

On western fires Haines Index values of 5 or 6 serve as an alert that fires or prescribed burns can experience control challenges. Local regional studies in North Carolina have shown that a Haines Index of 4 represents the initiating threshold whereby the atmosphere can support large fire growth. In the absence of strong winds, fire growth will be primarily "plume dominated", with crowning and spotting on all sides. As wind speeds increase, coupled with a starting Haines Index of 4 or greater, there is an increased threat for large wind-driven fires.

- Refers to the time and/or temperature at which the morning inversion will burnoff, or the time the inversion will setup in the evening. If the inversion is not surface based (yet still at low levels, e.g. below 1000 feet), meteorological factors other than nighttime radiational cooling may be taking place and as such, inversion information may not be given ("Inversion" remains in the forecast through the day, which would be reflected by a low mixing height). Conversely, there will be situations when a low level inversion does not develop at night; during these situations when a "NO INV" or "NONE" will be noted. Note: WFO's GSP and ILM will include burnoff time and temperature in the morning, as well as setup time in the evening. WFO MHX includes burnoff temperature only. Other inversion notation includes CONT (for continued inversion), and MIXED/HHMM (when and inversion mixes out at local time HH:MM.

Note: WFO's MRX and RNK do not produce an inversion forecast.

- It is recognized that the profile of wind speed with altitude on active fire days is an important factor in fire behavior. Certain profiles of wind speed marked by decreasing speed above a maximum or a jet within 1500 ft of the surface can cause fires to behave erratically when combined with a rapid decrease in air temperature with altitude on the order of 5.5 degrees F per 1000 ft. Appendix 4 describes these types of profiles (Adverse Wind Profiles) that contribute toward adverse fire behavior.

The WPA is included in the remarks section of zone groupings that include North Carolina non-mountain counties from March through May. At the request of one or more partner agencies, the WPA can be included at other times of the year during periods of high fire danger.

Note: WFO's MRX and RNK do not produce a wind profile analysis.

Update Criteria for the Fire Weather Planning Forecast

Fire Weather Point Forecast Matrix (PFW)

Product Overview and Issuance Criteria

The PWF provides a detailed prediction of elements for three days out at 3-hour intervals, including smoke management parameters through day 2, and a more general 3 to 7 day forecast without smoke management parameters. The winds given in this forecast are not terrain corrected winds. The PWF is issued twice daily, once during the morning (between 3:00 and 6:30 AM), and the other during the afternoon (between 2:00 and 4:00 PM). For an example and information on decoding the product click on PFW Guide.

Site Specific Wildland Fire Forecasts (Spot Forecasts)

Criteria

Contents

Procedures for Requesting a Spot Forecast

Spot forecasts will be prepared when requested by a user agency. Federal, state and local agencies may request spot forecasts in support of wildfire suppression or other emergencies where lives and/or property may be threatened. Due to the detailed and specific nature of this forecast product, it is imperative that the user provide the forecaster with necessary and sufficient information so that a reliable forecast can be prepared.

Requests for spot forecasts should be made using the web based spot forecast request form. This form, along with instructions on how to use it, are available on the fire weather web pages of the local NWS sites, which can be accessed at www.erh.noaa.gov. The web based spot forecast request form should be filled out as completely as possible by the user agency prior to submitting the request. In times when internet access is hindered or not possible, spot forecasts may be requested and disseminated via fax or phone. If faxing a request, users should use the Fire Weather Special Forecast Request Form, WS Form D-1. Section I of WS Form D-1 should be filled out as completely as possible by the user agency prior to submitting the request by the fax to the forecast office. If the request is made by phone, all information in Section I should be provided to the forecast office.

While there is no dedicated fire weather forecaster, the forecast office will give a high priority to spot forecasts in the absence of weather phenomena in the CWFA that pose a threat to life and property. To ensure that the request for a spot forecast is handled properly and appropriately, users should adhere to the following guidelines:

1) Allow adequate time for the forecaster to prepare the forecast. This will normally be between 20 and 30 minutes. On particularly busy fire weather days, spot forecasts will be handled on a first-come, first-serve basis, with wildfires or other life threatening events taking the highest priority.

2) Provide as much on-site or near-site weather information as possible. At a minimum, the user must provide at least one observation within an hour of the request. This observation must contain the following: location of the observation; elevation at the observation site; time of the observation; wind direction, speed, and level (eye or 20 foot); dry and wet bulb temperatures (or dry bulb temperature and relative humidity); any remarks about the state of the weather, particularly anything that may affect fire behavior. If possible, include some observations from the previous day that might give the forecaster an indication of daily trends.

3) As much as possible, specify the time period for which the forecast is needed.

4) As much as possible, specify the weather elements of most importance for which a forecast is needed, and/or critical values of these elements.

5) Provide a contact point name and phone number where the forecaster can call back, if necessary. (Also include a fax number for returning completed forecasts if the web based spot forecast form is not used).

6) In order to receive prompt attention for a fax request, please phone the office to let the forecaster know the request is on the way.

7) Natural resource agency personnel should contact the appropriate NWS forecast office for a spot update if the forecast conditions appear unrepresentative of the actual weather conditions. Whenever possible, users should provide feedback, positive or negative, to the NWS forecast office concerning the performance of the spot forecast during or shortly after an event. This will assist forecasters in subsequent forecasts for the same or similar conditions.

Click for example of spot request form D1.

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National Fire Danger Rating System (NFDRS) Forecasts

Issuance

Contents

The NFDRS forecast will be a forecast of the next day observation at 1300 LT. The format of the NFDRS forecast is specified in National Weather Service Directive 10-401. The forecast will include the following elements:

a. ZONE/FCTS: Shows whether this forecast is for an NFDRS zone or individual station. Zone average trends are forecast when enough observation are available for the zone area. Individual site forecasts are done where only a few observation are available.

b. NO: NFDRS Zone Number (or individual NFDRS site number).

c. YYMMDD: Year, month and day of valid forecast time.

d. 13: Valid forecast time. Always 1300 LST.

e. WX: Weather valid at 1300 LST tomorrow. Valid entries are:

0 = clear

1 = scattered clouds (1/8 to 4/8)

2 = broken clouds (5/8 to 7/8)

3 = overcast clouds (more than 7/8)

4 = fog

5 = drizzle

6 = rain

7 = snow or sleet

8 = showers (in sight or at the station)

9 = thunderstorm

(Categories 5, 6 or 7 sets NFDRS index to 0)

f. TEMP: Temperature in degrees F valid at 1300 LST (or temperature trend + or - degrees F).

g. RH: Relative Humidity in percent valid at 1300 LST (or RH trend + or - percent).

h. LAL1: Lightning Activity Level 1400 LST to 2300 LST.

i. LAL2: Lightning Activity Level 2300 LST to 2300 LST.

j. WDIR: Wind Direction. Used only for point forecast (FCST) version. Enter direction using sixteen point compass (N, NNE, NE, ENE, etc.) valid at 1300 LST (20 ft level, 10 minute average).

k. WSPD: Wind Speed. Enter wind speed in mph (or wind speed trend + or - mph) valid at 1300 LST (20 ft, 10 minute average).

l. 10HR: 10 hour timelag fuel moisture in percent valid at 1300 LST (or trend + or - percent).

m. Tx: Maximum temperature from 1300 LST to 1300 LST tomorrow.

n. Tn: Minimum temperature from 1300 LST to 1300 LST tomorrow.

o. RHx: Maximum relative humidity from 1300 LST to 1300 LST tomorrow.

p. RHn: Minimum relative humidity from 1300 LST to 1300 LST tomorrow.

q. PD1: Precipitation duration in hours 1300 LST to 0500 LST.

r. PD 2: Precipitation duration in hours 0500 LST to 1300 LST.

s. WETFLAG: Y or N. Indicates whether liquid water will be on the fuels at 1300 LST tomorrow. (Use with caution. A "Y" will set all the NFDRS indices to zero!).

Format. The NFDRS Forecast will follow the comma delimited format as shown:

ZONE,NO,YYMMDD,13,WX,TEMP,RH,LAL1,LAL2,WSPD,10HR,TX,TN,RHx,RHn,PD1,PD2,WETFLAG

FCST,NO,YYMMDD,13,WX,TEMP,RH,LAL1,LAL2,WDIR,WSPD,10HR,TX,TN,RHx,RHn,PD1,PD2,WETFLAG

Procedures

The land management agencies are responsible for taking, quality controlling, transmitting and archiving the NFDRS observations. Observation must be received at the NWS in a timely manner. Forecasts will only be prepared for predetermined sites, and only from those sites for which an observation has been received. The NWS will prepare and transmit the NFDRS forecasts no later than 4 PM. Although the data cutoff time for ingest into the NFDRS software is 7 PM, preliminary calculations based on the forecast are used by the land managers to make staffing decisions at shift briefing time (4 PM).

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Fire Weather Watch and Red Flag Programs

During periods in which critical fire weather conditions are expected or imminent, the NWS will issue statements, watches and warnings to describe the level of urgency to the appropriate user agencies. These issuances will be coordinated with natural resource agencies.

Definition of a Red Flag Event

Red Flag Warning

Fire Weather Watch

Fire Danger Statements and Blow-Up Alerts

Communications

The primary means of communication used by the NWS is the Advanced Weather Interactive Processing System (AWIPS). Products transmitted by this means include pre-suppression forecasts, Fire Weather Watches, Red Flag Warnings, and Fire Danger Statements. Spot Forecasts will be disseminated only to the requesting agency by means of the Internet, or as a backup, telefax (FAX). Therefore, anytime a request for a spot forecast is made, the requesting agency must include a FAX number. A voice number should also be included in case problems are encountered with the fax transmission. Other means of communication may be utilized upon mutual agreement with the user agencies.

Public products produced by the National Weather Service are available over All Hazards NOAA Weather Radio (NWR). See the Appendix for a listing of NWS transmitters serving North Carolina. (Map)

Participation in Interagency Groups

At a minimum, one NWS representative (usually the State Liaison WFO Fire Weather Program Leader or MIC) will attend the State Interagency meetings or working groups where fire weather or smoke management policy is discussed as an integral part of the meeting. However, it is strongly recommended that all NWS offices with fire weather responsibility attend the meetings to ensure uniform representation.

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Special Services

Special fire weather services are those services that are uniquely required by natural resource agencies and go beyond the normal forecast operations of the NWS. Special services include Incident Meteorologist (IMET) deployment, station visits, training, and other pertinent meteorological services that are designated as non-routine.

Typically, special services require NWS personnel to be away from the Forecast Office and, in some instances, be in overtime status. User agencies are responsible for covering the cost of NWS overtime, travel and per diem expenses. Reimbursement of costs for special services will be as outlined in the Interagency Agreement for Meteorological Services

Incident Support

On-site forecast service support is available for wildfires and prescribed burns. This includes the deployment of an Incident Meteorologist (IMET) and related service equipment such as the Advanced Technology Meteorological Unit (ATMU), the All Hazards Meteorological Response System (AMRS), and the Fire Remote Automated Weather Station (Fire RAWS). The IMET, ATMU, AMRS, and the Fire RAWS are considered national fire fighting resources, and can be requested through the North Carolina Interagency Coordination Center.

The ATMU and AMRS are modularized and mobile systems of equipment used by an Incident Meteorologist (IMET) for data collection and forecast preparation. Only trained personnel will operate the ATMU and AMRS, and this service equipment will only be dispatched to an incident when a certified IMET is requested. The IMET is responsible for ordering and arranging shipment for the ATMU and AMRS.

There are 25 ATMUs cached across the country, mostly in the western states. The nearest ATMU cache to the state of North Carolina is London, KY, where two are maintained. AMRS workstations are also pre-positioned across the country, most of which are collocated with existing Weather Forecast Offices that contain certified IMETS. These AMRS workstations are maintained by the IMETS and are typically shipped with the IMET being mobilized.

The ATMU is composed of one large shipping box consisting of a theodolite with tripod, a belt weather kit, PIBAL weather balloons, a nozzle and regulator for a helium tank, and office supplies and miscellaneous expendables. Its volume is 13.8 cubic feet and it weighs 122 pounds.

The AMRS is also composed of one large shipping box, and contains a laptop computer, a satellite dish (BGAN) for obtaining weather data, a printer and office supplies. The volume is 6.7 cubic feet, and its weight is about 90.

Total weight of the ATMU and AMRS is 212 lbs with a volume of 20.5 cubic feet. The cubic feet are necessary for shipment by air. The same specification shown are listed in the user agencies' National Mobilization Guide.

Requests for the ATMU, AMRS, and IMET should be made through the North Carolina Interagency Coordination Center. Typically, the IMET nearest the incident will be deployed. However, during times of limited resources, IMETs from other areas of the country may be called. The decision will be made by the Special Meteorologist to NIFC (SMC) in conjunction with the MIC and IMET from the affected offices. It is the responsibility of the IMET to arrange shipment of the AMRS workstation.

The success of the operation depends in part on the user agency providing shelter and logistical support. Prior to the use of this equipment, the IMET is expected to have coordinated with the local user agency to ensure proper field support. If an IMET determines that an ATMU and/or Fire RAWS is desirable, it is the IMET's responsibility to ensure the ATMU and Fire RAWS have also been ordered for the incident.

The requesting agency is responsible for any storage of service equipment while in transit, and shelter for the IMET and service equipment at the site. A sheltered work area, of at least 50 square feet with a table and chair, must be protected from excessive dust, free of standing water or condensation, and must be heated and/or cooled sufficiently to allow efficient operation of equipment. Power (120V AC) must be provided for the AMRS's electrical equipment, and priority telephone access during certain short periods each day must be made available.

The procedure for requesting IMETs will follow the guidelines outlined in the national MOA, the National Mobilization Guide, and the Southern Area Interagency Mobilization Guide. The following information will be provided to the requested IMET:

1. Name of fire.

2. Location of fire.

3. Directions to location where the IMET is to report and the location of ICP.

4. Name of Incident Commander, Plans Chief, and FBAN, if available.

5. Request and Resource Order number for IMET.

Upon arrival at the incident and after going through the appropriate check-in procedures, the IMET will:

1. Brief the Fire Behavior Analyst (FBAN), Planning Section Chief (PSC), and the Incident Commander (IC) on current and expected weather as it affects the fire.
2. Establish a schedule with the IC and the FBAN for written forecasts and formal briefings.
3. Request a briefing of the fire situation and potential behavior problems from the FBAN. As time and resources permit, incident management should arrange for an aerial inspection trip for the meteorologist and should provide the forecaster with current fireline maps. If possible, the IMET should be assigned a radio with the fireline frequency.
4. Arrange for a schedule of observations from key points around the fire and from nearby lookouts and fire danger stations, in cooperation with the FBAN and PSC. On large fires, some personnel (at least two) should be permanently assigned to this duty. On smaller fires, this information can be provided by Division Supervisors equipped with belt weather kits.

IMET duties will vary with incident management team requirements, but the IMET is expected to provide daily weather forecasts for the incident, participate in shift briefings, planning and strategy meeting, and coordinate daily with the local Weather Forecast Office (WFO) and /or other IMETs at nearby incidents.

Demobilization is initiated at the incident, and will be coordinated through the North Carolina Interagency Coordination Center. Upon release, the user agency will transport the ATMU and Fire RAWS back to its cache location or to the controlling fire weather office. Travel arrangements will be made for the IMET back to his or her home office. The IMET is responsible for transporting the AMRS workstation back to the home office. If the AMRS unit resides at a different location than the IMET, the IMET must make arrangements to ship the equipment to the proper office, and charge any shipping cost to the fire.

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Other Special Services

Other special services may include weather station visits by partner agency personnel, RAWS site surveys and inspections, weather observer training, and course development work or related program work. These activities would typically be at the full expense of the requesting agency unless other arrangements have been made.

NWS meteorologists may also be asked to assist in other non-routine services (e.g. briefings or coordination calls) during periods of high fire danger or fire occurrence. MICs and Fire Program Leaders are to ensure the natural resource agency needs are met with little expense to either agency.

Fire Weather Training

NWS meteorologists will be available to assist in user-oriented training. This includes fire behavior courses, such as S-190 and S-290, where the meteorologist will serve as part of the cadre for that course. Requests for training assistance should be made through the NWS office's Fire Weather Program Leader or Meteorologist-in-Charge (MIC). Sufficient advance notice should be given to allow for scheduling and proper preparation. Costs incurred by the NWS in providing training assistance will be borne by the requesting agency.