SKYWARN Reporting Criteria

The following is SKYWARN reporting criteria that should be followed and the type of reports that should be gathered across the entire SKYWARN network via Amateur Radio.

• Tornadoes or funnel clouds (be very wary of look-alikes; watch for rotation)

• Wall clouds, especially if they are rotating

• Hail (Be specific with regard to size; DO NOT report MARBLE size)

• Winds (40 mph or greater; specify whether estimated or recorded)
— large branches downed (specify diameter of branch)
— Trees/power lines downed
— Structural damage to buildings (roof, windows, etc.)

• Rainfall
— 1 inch or greater in an hour (NOT a 1″/hr. rate for 10 minutes)
— 2 inches or greater storm total

• Flooding
— Streams/Rivers — also, when nearing bankful
— Coastal
— Street (Road Closures/Washouts, Cars Stuck due to flood waters. Minimum of 6″ of water covering an entire roadway or lane of a major route/highway)

• Winter Weather
— Precipitation type change (rain to sleet/freezing rain/snow,
when the change has “taken hold”)
— Thunder, when accompanied by snow
— 1/4″ radial ice accretion (from twig outward; not circumference)

• New Snowfall
— First 2 inches; every 2-3 inches thereafter
— 1 inch per hour or greater
— If less than 2 inches total, give final total only
— Give final total (don’t leave us hanging with a partial report)
— Report any snow/sleet/freezing rain if not in NWS forecast!

PROCEDURES
1) Advise Amateur Operators to BRIEFLY describe WHAT was observed; and WHEN &
WHERE it was observed.
2) Make sure hail size is noted using proper conventions (NO Marble Sized Hail).
3) Make sure if winds are estimated that they use estimates as taught in
SKYWARN training.

The following is SKYWARN reporting criteria that should be followed and the type of reports that should be gathered across the entire SKYWARN network via Amateur Radio.

• Tornadoes or funnel clouds (be very wary of look-alikes; watch for rotation)

• Wall clouds, especially if they are rotating

• Hail (Be specific with regard to size; DO NOT report MARBLE size)

• Winds (40 mph or greater; specify whether estimated or recorded)
— large branches downed (specify diameter of branch)
— Trees/power lines downed
— Structural damage to buildings (roof, windows, etc.)

• Rainfall
— 1 inch or greater in an hour (NOT a 1″/hr. rate for 10 minutes)
— 2 inches or greater storm total

• Flooding
— Streams/Rivers — also, when nearing bankful
— Coastal
— Street (Road Closures/Washouts, Cars Stuck due to flood waters. Minimum of 6″ of water covering an entire roadway or lane of a major route/highway)

• Winter Weather
— Precipitation type change (rain to sleet/freezing rain/snow,
when the change has “taken hold”)
— Thunder, when accompanied by snow
— 1/4″ radial ice accretion (from twig outward; not circumference)

• New Snowfall
— First 2 inches; every 2-3 inches thereafter
— 1 inch per hour or greater
— If less than 2 inches total, give final total only
— Give final total (don’t leave us hanging with a partial report)
— Report any snow/sleet/freezing rain if not in NWS forecast!

PROCEDURES
1) Advise Amateur Operators to BRIEFLY describe WHAT was observed; and WHEN &
WHERE it was observed.
2) Make sure hail size is noted using proper conventions (NO Marble Sized Hail).
3) Make sure if winds are estimated that they use estimates as taught in
SKYWARN training.