AT 209 Lab 10: Weather Briefings

Introduction

Weather briefings are critical for flight, whether that be for commercial aviation, private, or UAS. They can make or break a planned flight depending on the conditions. To better inform pilots or operators on the conditions, METARs, TAFs, and AIRMETs were created to create an easy and quick way to get a briefing. Lab 10 consists of decoding these means of weather briefings and what they mean.

Methods

To conduct Lab 10, students were required to find a METAR, TAF, and AIRMET of the area around Purdue University Airport (LAF or KLAF). Using the Aviation Weather Center's (AWC) website and Skyvector's aeronautical sectional charts, the METAR, TAF, and AIRMET were obtained for the current time. Below the Discussion portion of the post will show what they all look like and the type of information that is within those means.

Discussion

Below, Figure 1 will look at the METAR and TAF. Below, they are deciphered line-by-line.

Figure 1: Above is the METAR followed by the TAF.

The METAR will be represented by the line and spaced respectively to decipher the information it holds:

• Line 1 (& Only line):
• Purdue University Airport (KLAF = Indicator)    Nov. 4th 1554 Zulu (Issued time)    240 degrees from true north (Direction of wind), 13 knots (Speed of wind) with gusting 21 knots (Speed of gusts)    Visibility of 10 statue miles    Clear skies at or below 12,000 feet AGL (No clouds above indicated level above ground level)    Temperature of 11 Celsius, 3 Celsius dew point    Altimeter set to 30.01 inches    Remarks (RMK): Automated with precipitation sensor    Sea level pressure (SLP) at 1,016.4 hPa    Temperature at 10.60 Celsius, 2.8 Celsius dew point

The TAF will be represented line-by-line to understand what it means:

• Line 1:
• Purdue University Airport    Nov. 4th, 1505 Zulu    TAF valid from Nov. 4th at 1500 Zulu to Nov. 5th 1200 Zulu   Winds 220 degrees from true north, 10 knots with gusting 16 knots    Visibility above 6 statue miles    Few clouds at 20,000 feet AGL
• Line 2:
• From Nov. 4th, 1800 Zulu    Winds 230 degrees from true north, 13 knots    Visibility above 6 statue miles    Broken clouds at 6,000 feet AGL
• Line 3:
• From Nov. 4th, 2300 Zulu    Winds 250 degrees from true north, 9 knots    Visibility above 6 statue miles    Broken clouds at 10,000 feet AGL
• Line 4:
• From Nov. 5th, 500 Zulu    Winds 290 degrees from true north, 7 knots    Visibility above 6 statue miles    Broke clouds at 7,000 feet AGL

Figure 2: The area of the AIRMET is shown from the sectional chart above. All airports marked by the different colored pins.

When looking up the information associated to the AIRMET, you get a result of below (Lines numbered for reference):

WAUS43 KKCI 080046 AAC 
CHIT WA 080046 AMD 

AIRMET TANGO UPDT 8 FOR TURB VALID UNTIL 080300 
AIRMET TURB...MN IA MO WI LM MI LH IL IN 
FROM 60N RHI TO 30NW TVC TO 60NW YVV TO 30SE ECK TO FWA TO 50WSW 
ROD TO 20S STL TO 30ESE OVR TO 50SE FSD TO 60SE BRD TO 60N RHI 

MOD TURB BTN FL180 AND FL370. CONDS CONTG BYD 03Z THRU 09Z. 
OTLK VALID 0300-0900Z 

AREA 1...TURB MN IA WI LM LS MI LH IL IN 
BOUNDED BY 70ESE YQT-YVV-30SE ECK-FWA-40WSW ROD-40S JOT-30ESE 
DBQ-20W ODI-50N EAU-70ESE YQT 

MOD TURB BTN FL180 AND FL370. CONDS CONTG THRU 09Z. 
AREA 2...TURB ND SD NE KS 
BOUNDED BY 50S YWG-60N FSD-20SSE OBH-GLD-70SW RAP-50NNW ISN-50S 
YWG 

MOD TURB BTN FL240 AND FL410. CONDS CONTG THRU 09Z. 
AREA 3...TURB NE KS IA MO IL IN KY OK TX AR TN LA MS AL...UPDT 
BOUNDED BY 40ESE DBQ-40S JOT-40WSW ROD-CVG-HNN-HMV-GQO-40WSW PZD- 
40NNW CEW-40E MCB-AEX-20NNE LFK-20ESE ACT-INK-30ESE TBE-40WSW 

MOD TURB BTN 170 AND FL430. CONDS CONTG THRU 09Z.
LBL-50SE LAA-GLD-40ESE PWE-40ESE DBQ

Yes, this is very lengthy and data enriched. For the sake of discussion, Lines 3-11 will be focused on. 

• Line 3: AIRMET updated for turbulence and valid until Nov. 8th, 300 Zulu
• Line 4: AIRMET for turbulence followed by affected states (Indiana included)
• Lines 5-6: Defines the area covered by the AIRMET - 60 nautical miles north of Rhineland VOR (Abbreviations mean VOR or VORTAC stations), 30 nautical miles northwest of Traverse City VOR, 60 nautical miles northwest of Wiarton VOR, 30 nautical miles southeast of Peck Tacan VOR, Fort Wayne VORTAC, 50 nautical miles west/southwest of Rosewood VORTAC, 20 nautical miles south of St. Louis VORTAC, 30 nautical miles east/southeast of Omaha VORTAC, 50 nautical miles southeast of Sioux Falls VORTAC, 60 nautical miles southeast of Brainerd VORTAC, 60 nautical miles north of Rhineland VOR
• Line 7: Moderate turbulence between 18,000 and 37,000 MSL, Conditions beyond 300 through 900 Zulu time
• Line 8: Outlook valid from 300 through 900 Zulu time
• Line 9: The turbulence AIRMET is defined into areas, Indiana is included in Area 1
• Lines 10-11: Bounded by 70 nautical miles east/southeast of Thunder Bay VOR and Wiarton VOR, 30 nautical miles southeast of Peck Tacan VOR and Fort Wayne VORTAC, 40 nautical miles west/southwest of Rosewood VORTAC, 40 nautical miles south of Joliet VOR, 30 nautical miles east/southeast of Dubuque VORTAC, 20 nautical miles west of Nodine VORTAC, 50 nautical miles north of Eau Claire VORTAC, 70 nautical miles east/southeast of Thunder Bay VOR

Conclusion

As mentioned, the three types of means are very important and hold a lot of information about the weather and surrounding area They are essential for flight planning in both aviation and the UAS realm. Relating to UAS, all three of the means give the operator on what to expect for that particular time and day. When operating a UAS, the operator must be aware of the weather and the effects it has on the system, whether that be waterproofing, securing equipment, or ultimately cancelling the operation. It is significant for operators to be aware of the weather before operating to perform operations in safe conditions.