Category Archives: Crazy weather events

Weather meant for flying a … desk

images

Ick

TAF CYTZ 080148Z 0802/0902 06025KT 1SM -SN BLSN OVC008 TEMPO
0802/0803 3SM -SN OVC010
FM080300 06025KT 6SM -SN OVC010 TEMPO 0803/0806 3SM -SN OVC008
PROB30 0803/0806 2SM -SN -FZDZ BR OVC005
FM080600 06020KT 3SM -SN OVC010 TEMPO 0806/0808 11/2SM -SN OVC008
PROB30 0806/0808 3/4SM -SN BLSN
FM080800 06020KT 3/4SM -SN OVC008
FM081100 06020KT 1/2SM SN VV005 TEMPO 0811/0821 1/4SM +SN BLSN
VV002
FM082200 02020G30KT 11/2SM -SN BLSN OVC012 TEMPO 0822/0824 3/4SM
-SN BLSN VV008
FM090100 35020G30KT 3SM -SN BLSN OVC015
RMK FCST BASED ON AUTO OBS. NXT FCST BY 080800Z=

Pilot types will recognize the above information as a TAF. For non-pilots, a TAF is weather forecast. TAF stands for Terminal Aviation Forecast. It’s a tool used to predict weather at a given airport. The TAF shows the weather at an airport for a radius of five statute miles.

I’ve provided below the translation of the TAF I’ve included here. It shows the weather at Toronto’s Billy Bishop (Island) Airport, an commuter airport located near Toronto’s downtown. It’s about an hour-and-change drive from my home.

This particular TAF, issued at 08:48 p.m. Eastern time (01:48 in the morning, Universal Time Coordinated), on the night of Thursday, Feb., 7, 2013, depicts weather that is, well, pretty ugly, commensurate with the nasty storm due to roll through southern Ontario and much of the U.S. northeast. Cloud ceilings are low, Visibility is terrible. Lots of blowing snow. And what’s striking is how often the conditions are forecast to shift through the night. Not the kind of stuff you want when landing an airplane.

Some translations of the translation:

  • SM means Statute Miles, and refers to the miles of visibility.
  • Z means Zulu Time, or Universal Time Coordinated.
  • The numbers after the word “Overcast” state the cloud ceiling, so Overcast 800′ means the ceiling is at 800 feet above the ground.
  • The numbers that look like this: 060° 25 KT, depict the wind direction and speed. In this case it means the wind is blowing from the direction of 060 true degrees, or northeast, and at a strength of 25 nautical miles per hour.
  • IFR means Instrument Flight Rules.
  • VFR means Visual Flight Rules.
  • MVFR means Marginal Visual Flight Rules.
  • LIFR means Limited Instrument Flight Rules.
Reported
Fri, Feb 8, 01:48 Z
Valid
Fri, Feb 8, 02:00 Z – Sat, Feb 9, 02:00 Z
Initial Weather
Light Snow, Blowing, Snow
Overcast 800′
1 SM
060° 25 KT
MVFR
Temporary 2:00 – 3:00 Z
Light Snow
Overcast 1,000′
3 SM
MVFR
3:00 Z
Light Snow
Overcast 1,000′
6 SM
060° 25 KT
MVFR
Temporary 3:00 – 6:00 Z
Light Snow
Overcast 800′
3 SM
IFR

3:00 – 6:00 Z
Light Snow, Freezing, Drizzle, Mist
Overcast 500′
2 SM
MVFR
6:00 Z
Light Snow
Overcast 1,000′
3 SM
060° 20 KT
IFR
Temporary 6:00 – 8:00 Z
Light Snow
Overcast 800′
11/2 SM
LIFR
6:00 – 8:00 Z
Light Snow, Blowing, Snow
3/4 SM
IFR
8:00 Z
Light Snow
Overcast 800′
3/4 SM
060° 20 KT
LIFR
11:00 Z
Snow
Vertical Vis. 500′
1/2 SM
060° 20 KT
LIFR
Temporary 11:00 – 21:00 Z
Heavy Snow, Blowing, Snow
Vertical Vis. 200′
1/4 SM
MVFR
22:00 Z
Light Snow, Blowing, Snow
Overcast 1,200′
11/2 SM
020° 20 KT Gusts 30 KT
LIFR
Temporary 22:00 – 0:00 Z
Light Snow, Blowing, Snow
Vertical Vis. 800′
3/4 SM
MVFR
01:00 Z
Light Snow, Blowing, Snow
Overcast 1,500′
3 SM
350° 20 KT Gusts 30 KT
In short, get your snow shovel out.