In the summer time, it is not uncommon to see TFR’s for “Hazard” due to fires. The actual TFR is often times the least of the issues since:
1. they are often small, e.g. a radius of 10 miles of less,
2. they are plotted via various apps/systems such as ForeFlight, G1000, as well as the sectional view on www.faa.gov.
3. and you can create a plan to avoid them.
The greater hazard is the smoke and haze generated from these fires. The smoke and associated haze reduce flight visibility and in some cases dramatically so. In addition, the haze can cause strain on your eyes because all you see is a wall of white. Probably the biggest challenge is that it is hard to know where the smoke will be both from a geographical area as well as how high the smoke goes. Smoke may not easily show on a satellite image if it is below a cirrus cloud layer. Area forecasts often only provide broad indications of where smoke (FU) might be found and then only if the visibility is less than 5 SM. So if the visibility is 6 or 7 SM, which is still pretty poor, the area forecast won’t report the smoke like the examples below.
OR CASCDS WWD
SWRN INTR...BKN CI. OCNL VIS 3-5SM FU. FU TOP 120. 21Z SCT CI OCNL VIS 3-5SM FU. OTLK...VFR FU.
NRN CA...STS-SAC-TVL LN NWD
SHASTA-SISKIYOUS...BKN CI. OCNL VIS 3-5SM FU. FU TOP 120. 21Z SCT160. ISOL -TSRA. CB TOP FL400. OTLK...VFR TIL 02Z TSRA.
CNTRL CA
SAN JOAQUIN VLY...SKC. TIL 20Z OCNL VIS 3-5SM HZ/FU. FU TOP 055 OTLK...VFR.
Sometime the best sources of information are pilot reports. But often times, they are not very many pilot reports to be helpful. But when they do exists, like the ones below, they can be valuable information if they happen to be near your intended route of flight.
LMT UA /OV 2S2 /TM 2010 /FL109 /TP C185 /SK TOP105 /WX HZ FU
MFR UA /OV FJS-OED180020/TM 2234/FL100/TP C310/WX FV01SM HZ/RM IMC
Lastly, sometimes an AIRMET may help identify an area that is obscured by smoke but AIRMETs technically have a threshold that the weather phenomenon has to be impacting an area of at least 3,000 square miles. In the cases below, they do help pinpoint area where visibility will be poor.
WAUS46 KKCI 311445
SFOS WA 311445
AIRMET SIERRA UPDT 3 FOR IFR AND MTN OBSCN VALID UNTIL 312100
AIRMET MTN OBSCN...OR CA
FROM 60SE EUG TO 50ESE OED TO 70SW OED TO 50S EUG TO 60SE EUG
MTNS OBSC BY FU/HZ. CONDS CONTG BYD 21Z THRU 03Z.
WAUS46 KKCI 311445
SFOS WA 311445
AIRMET SIERRA UPDT 3 FOR IFR AND MTN OBSCN VALID UNTIL 312100
AIRMET IFR...OR CA
FROM 40NNW OED TO 20NW LKV TO 80SSW LKV TO 50E FOT TO 40NNW OED
VIS BLW 3SM HZ/FU. CONDS ENDG 18-21Z.
Wednesday, July 31, 2013
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