4/20/23 

AIM 

When cloud

−

to

−

ground lightning is detected by an automated lightning detection system, such as ALDARS: 

[a] 

Within 5 nautical miles (NM) of the Airport Reference Point (ARP), it will be reported as “TS” 

in the body of the report with no remark; 

[b] 

Between 5 and 10 NM of the ARP, it will be reported as “VCTS” in the body of the report with 

no remark; 

[c] 

Beyond 10 but less than 30 NM of the ARP, it will be reported in remarks as “DSNT” followed 

by the direction from the ARP. 

EXAMPLE

−

 

LTG DSNT W or LTG DSNT ALQDS 

(11) 

Beginning/Ending of Precipitation/TSTMS. 

(12) 

TSTM Location MVMT. 

(13) 

Hailstone Size (GR). 

(14) 

Virga. 

(15) 

VRB CIG (height). 

(16) 

Obscuration. 

(17) 

VRB Sky Condition. 

(18) 

Significant Cloud Types. 

(19) 

Ceiling Height 2nd Location. 

(20) 

PRESFR PRESRR. 

(21) 

Sea

−

Level Pressure. 

(22) 

ACFT Mishap (not transmitted). 

(23) 

NOSPECI. 

(24) 

SNINCR. 

(25) 

Other SIG Info. 

(c)  Additive and Automated Maintenance Data. 

(1) 

Hourly Precipitation. 

(2) 

3

−

 and 6

−

Hour Precipitation Amount. 

(3) 

24

−

Hour Precipitation. 

(4) 

Snow Depth on Ground. 

(5) 

Water Equivalent of Snow. 

(6) 

Cloud Type. 

(7) 

Duration of Sunshine. 

(8) 

Hourly Temperature/Dew Point (Tenths). 

(9) 

6

−

Hour Maximum Temperature. 

(10) 

6

−

Hour Minimum Temperature. 

(11) 

24

−

Hour Maximum/Minimum Temperature. 

(12) 

Pressure Tendency. 

Meteorology 

7

−

1

−

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