This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: F 1 August 24, 2007 UPPER-LEVEL PRESSURE, TEMPERATURE, HUMIDITY AND WIND REPORT I. GENERAL The WMO upper-level pressure, temperature, humidity, and wind report is called FM 35-IX Ext. TEMP for reports from land stations; FM 36-IX Ext. TEMP SHIP for reports from sea stations; FM 37-IX Ext. TEMP DROP for sondes released by a carrier balloon or an aircraft; and FM 38-IX Ext. MOBIL for mobile land stations. The code form is divided into four parts (i.e., Parts A, B, C, and D) for coding purposes. The coding procedures provide for coding each part as a separate message suitable for transmission. Each part can be transmitted separately but the complete report actually consists of four separate messages which may be collected individually in a bulletin, or in combinations. ________________________________________________________________________ A. TIME OF OBSERVATION The standard times of upper-air soundings taken for synoptic purposes are 0000, 0600, 1200, and 1800 UTC. If only two upper-air soundings are taken per day for synoptic purposes, they shall be taken at 0000 and 1200 UTC. In the case of upper-air observations, the actual time of observation is the time the balloon is actually released to the nearest minute. The standard time of observation is the synoptic time, to the nearest whole hour, to which the sounding applies. International agreement specifies that the time of regular upper-air sounding observations should be as close as possible to (H-30) and should not fall outside the time range (H-45) to (H), with H referring to one of the four standard synoptic times of observations. Thus, the actual time of release of a balloon might be 1130 UTC, but the observation applies to 1200Z. It should be noted that the time required for a radiosonde balloon to reach 90,000 feet is approximately 1 1/2 hours. Thus measurements of elements from high elevations may be an hour to 1 1/2 hours after the actual time of observation. Special observations may be made outside these specified release times when authorized. ________________________________________________________________________ II. FORMAT OF THE UPPER-AIR REPORT The upper-air report message is composed of five-figure groups. Each figure in each group has significance according to its position in the group and according to its position in the message following the section indicator. Thus, when data is not available for an element, or position, the missing position will be filled with a solidi (/). The code form is divided into ten sections as follows: F 2 August 24, 2007 Section Indicator figures or Contents number symbolic figure groups 1 Identification and position data....
View Full Document
This note was uploaded on 04/02/2008 for the course ATMO 251-501/50 taught by Professor Alcorn during the Spring '07 term at Texas A&M.
- Spring '07