Weather Information

Question 1

What is HIWAS?

Answer 1

Hazardous Inflight Weather Advisory Services
- Provides a continuous broadcast of of wx advisories including: SIGMETS, Convective SIGMETs, urgent PIREPs

• It’s an additional source of hazardous weather information, which makes it available on a continuous basis

Question 2

Why kind of weather can you expect from a cold front?

Answer 2

• Crappy weather with cumulus clouds
• Low visibility
• TS/squall lines

Question 3

Why kind of weather can you expect from a warm front?

Answer 3

• Good visibility
• Stratiform clouds
• Showery precipitation

Question 4

How often are convective SIGMETs good for, and what kind of weather can be expected?

Answer 4

• Valid for up to 2 hours
• Issued for severe TS due to:
  1. Surface winds greater than or equal to 50 knots
  2. Hail at surface greater than or equal to 3/4”
  3. Tornadoes
  4. Embedded TS
  5. Line of TS
  6. TS that produce precip levels greater than or equal to heavy-intensity, affecting 40% or more of an area at least 3,000 square miles

Question 5

How long are SIGMETs valid for after issued?

Answer 5

• 4 hours

Question 6

What weather phenom can be expected with SIGMETs?

Answer 6

• Severe icing not associated with TS
• Severe/extreme TB or CAT not associated w/ TS
• Dust storms or sand storms lowering vis to below 3 miles
• Volcanic ash

Question 7

What would AIRMET Tango would be issued for?

Answer 7

• Moderate TB
• Wind speeds of 30 knots or greater
• Non-convective LL wind shear

Question 8

What is a Convective Outlook?

Answer 8

A graphical outlook of the potential for severe & non-severe convection and specific severe weather threats during the following 8 days.

Question 9

How often are TAF’s issued, and how long are they good for?

Answer 9

• Issued 4x a day
• Valid for 24hrs
• Different types of TAFs include: Routine (TAF), Amended TAF AMD), Corrected (TAF COR)

Question 10

What information do you get from TAFs?

Answer 10

• Wind
• Visibility
• Significant/Vicinity wx
• Cloud/vertical obscuration
• Non-convective LLWS
• Forecast change indicators (FM, TEMPO, PROB)

Question 11

What type of wx would a Convective SIGMET be issued for?

Answer 11

Issued for:
Severe TS due to:
- SFC Winds _>/= to 50kts
- Hail at SFC >/= 3/4” in diameter
- Tornadoes

Embedded TS

Squall Lines

TS producing:
- Precip _>/= heavy-precipitation affecting
- 40% or more of
- at least 3,000 sq miles