MANOBS Manual of Surface Weather Observations: foreword

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This manual prescribes the standard procedures of the Meteorological Service of Canada for observing, recording and reporting weather conditions. It has been prepared in accordance with internationally recommended procedures as established by the World Meteorological Organization (WMO).

Amendments will be issued when warranted. All holders of the manual are responsible for keeping their copies current. When amendments have been entered, this fact should be recorded on the page headed Record of amendments.

Inquiries on the content of this manual should be directed to the Meteorological Service of Canada through appropriate channels.

This supplement contains the amendments adopted by the Manual of Surface Weather Observations (MANOBS) Working Group.

Note(1): Amendment 19 will implement the following requirements:

  • A full element special weather report (SPECI) as specified in the WMO Manual on Codes Volume 1.I, International Codes 2011 edition updated in 2012. FM 16-XII requires a full element SPECI.
  • Remove the standard for the reporting of Recent Weather (RE) phenomena in Aviation Routine Weather Report (METAR) and SPECI to comply with International Civil Aviation Organization (ICAO) Annex 3 Eighteenth Edition July 2013, Appendix 3 Section 4.8.1.1 removal of the requirement for Recent Weather (RE) phenomena where METAR/SPECI are issued.
  • Inclusion of Observer Circulars OBS 1-2012, OBS 1-2013 and OBS 2-2013.
  • Update to Appendix "V" for the Instrument Flight Rules (IFR) Approach and Alternate Limits for Canadian Aerodromes.

Note (2): Following consultation between Environment Canada, NAV CANADA, and the Department of National Defense in February 2015, it was agreed that necessary modifications to MANOBS would be applied in the form of an addendum. The addendum to MANOBS 7th Edition, Amendment 19, is effective as of May 2016. Effected sections are listed within the Record of Revisions.

Record of revisions

Miscellaneous corrections

  • 1.4.1; 1.4.2; 1.4.3; 1.4.4 - Added reference to oktas (Effective May 2016)
  • 1.8.3.1 - Added subsection to section 1.8.3: "Data from the Ceilometer shall be correlated with visual observations to determine cloud amount and to ensure that the cloud height is representative of the layer."
  • 3.9.5 - Replaced the term "Visibility" with "Intensity"
  • 5.1.3.1 - Updated Maximum Correction Card
  • 5.1.3.2; 5.1.3.3 - Revised to match Maximum Correction Card
  • 7.7 - Updated Beaufort Scale of Wind
  • 8.2.10.1 - Removed requirement for completion of column 42a on form 63-2322 (Effective May 2016)
  • 10.2.8.8 - Removed the wording: "... or when the ceilometer is inoperative"
  • 10.2.10.1 - Added (Visibility > 6mi.) (Effective May 2016)
  • 10.2.10.3 (7) - Revised item seven to read: "Additional phenomena and vicinity phenomena"
  • 10.2.10.8; 16.3.8.6.2 - Added paragraph to section: "To meet Canadian standards, when ice crystals (IC) are observed it shall be reported in the METAR/SPECI with any visibility." (Effective May 2016)
  • 10.2.19.8.1 - Removed sentence: "It is very important to report CB in remarks when it is observed but it is not the predominant cloud type."
  • 10.6.1 - Changed hour 13:00 UTC wind from 0201 to 0000 (Effective May 2016)
  • 16.3.3 - Example (2): Added TCU to sky condition and remarks (Effective May 2016)
  • 16.3.6.2 - Example (2): Changed altimeter from A2989 to A2948 (Effective May 2016)
  • 16.3.7.1 - Changed Altimeter from A2992 to A3002 in example (Effective May 2016)
  • 16.3.8.3 - Example (1): Changed light rain showers (-SHRA) to light rain (-RA) (Effective May 2016)
  • 16.3.8.4 - Changed proximity to vicinity in the heading and first sentence
  • 16.3.8.5 - Changed example for shallow fog visibility from 5SM to 7SM.
    Added remark CVCTV CLD EMBD to example for rain showers. (Effective May 2016)
  • 16.3.8.8 - Examples (3) and (6): Changed moderate rain to moderate rain showers.
    Added Remark HAIL DIAM 12 MM to SPECI. (Effective May 2016)
  • 16.3.9.8 - Example (3): SLP changed from SLP14 to SLP140
    Example (9): Dew point changed from 19 to 22
    Example (11): Dew point changed from 16 to 20
    Added Example (12) (Effective May 2016)
  • 16.3.13 - Changed example light rain showers (-SHRA) to light rain (-RA) (Effective May 2016)
  • 16.3.13.2.1 - Changed wind remark from 05007 to 05009 (Effective May 2016)
  • 16.3.13.2.2 - Added visibility Remarks for BCFG, MIFG and FG BANK (Effective May 2016)
  • 16.3.13.2.3 - Changed weather Remark CLR to SKC (Effective May 2016)
  • 16.3.13.2.3 - Note (4): Added guide for the frequency of lightning (Effective May 2016)
  • 16.3.13.2.7 - Revised rainfall Remarks for a clearer explanation (Effective May 2016)
  • 16.4.3 - Revised for clarification on transmission time of a SPECI (Effective May 2016)
  • 16.4.4.7 - Changed example for Remark INMT to INTMT (Effective May 2016)
  • 16.4.4.11 - Revised fourth point to read: "Immediately upon learning of an aircraft accident, at or in the vicinity of the weather observing station. The observer shall make an Accident Observation unless a complete METAR has been issued subsequent to the accident. The Accident Observation shall be as complete and accurate as possible, with particular care being taken to include in "Remarks" any meteorological facts that might relate to the accident, or which might be of significance to the aircraft accident investigator."
  • Appendix IV - Removed

Full element SPECI

  • 10.3.4 - Revised section to read: "An observation shall be taken promptly to report changes which occur between scheduled transmission times. A SPECI observation shall include the following:
    - Sky condition
    - Visibility
    - Weather and obstruction to vision
    - Sea level pressure
    - Temperature
    - Dew point
    - Wind
    - Altimeter setting
    - Clouds
    - Remarks (if required)
    - Runway Visual Range (RVR) (where available)"
  • 10.3.7.1 - Revised note to read: "If any of the observed elements warrant a SPECI, as defined in Section 10.3.4 (Criteria for taking a SPECI), a SPECI shall be transmitted and recorded on Form 63-2322."
  • 10.6 - Added full element SPECI for all SP examples on Form 63-2322

Pilot Report (PIREP)

  • 14.3.1(6) - Revised to read: "Low-level wind shear 1500 feet AGL and below."
  • 14.4.4 - Changed ICAO documentation reference to "ICAO DOC 8643 - Aircraft Type Designators"
  • 14.4.15 - Revised to read: "A pilot report of low-level wind shear 1500 feet AGL and below will be recorded in the Remarks (/RM) field of the PIREP and will be transmitted as an Urgent PIREP."
  • 14.4.16 - Inserted new sub-section: No turbulence or icing encountered
  • 14.5 - Example (3): Changed Whitehorse FSS to Whitehorse FIC (Effective May 2016)
  • 16.4.4.11 - Added "when a pilot reports wind shear in the lower layers (see 16.3.12)" (Effective May 2016)

Wind Shear

  • 10.2.19.6.4 - Revised to read: "Wind shear information on the existence of wind shear 1500 feet AGL and below along the take-off path or approach path of runway significant to aircraft operations shall be reported in Column 41 (Remarks) whenever available and local circumstances so warrant. The information will be reported in the following format:
    - When wind shear is reported on take-off or landing on one runway 1500 feet AGL and below it will be reported as: WS RWY DRDR (Official Runway Designation); or
    - When wind shear is affecting all runways 1500 feet AGL and below, it will be reported as: WS ALL RWY"
  • 16.3.12 - Revised to read: "Information on the existence of low-level wind shear along the runway takeoff or approach path 1500 feet AGL and below that is considered significant to aircraft operations shall be reported."

Recent Weather

  • 10.2.10.1 - Removed Recent Phenomena from table listing weather and obstruction to vision symbols for Column 32
  • 10.2.10.3 (7) - Revised item seven to read: "Additional phenomena and vicinity phenomena"
  • 10.2.10.4 - Revised to read: "Record in Column 32 only those phenomena which are occurring at the station, in the vicinity of the station, at the time of observation with the following exceptions: ..." Removed first part of second paragraph containing recent weather reporting procedures.
  • 10.2.19.4 - Removed Remark RERA
  • 10.6 - Removed all references to recent weather phenomena from Form 63¬2322 examples 1 and 2.
  • 16.2 - Removed reference to Recent Weather code REw'w' from Symbolic form of the Canadian METAR code.
  • 16.3.12 - Removed reference to: Recent Weather (RE) of operational significance
  • 16.3.12.1 - Removed reference to: List of Recent Weather (RE) phenomena in Appendix III
  • 16.3.12.2 - Removed section 16.3.12.2
  • Appendix III - Removed all references to recent weather (RE) phenomena

Sky Condition

  • 1.7.1 - Removed opacity and replaced with amount to determine ceiling (Effective May 2016)
  • 1.7.2 - Added oktas for ceiling definition (Effective May 2016)
  • 10.2.18.1 - Revised to read: "When a layer consists of two or more types, e.g., SC and CU, the predominating type by amount shall be recorded. If a cloud layer consists of any amount of TCU or CB, the TCU or CB shall be reported as the predominant type. However when an individual layer of cloud is composed of Cumulonimbus (CB) and Towering Cumulus (TCU) with a common cloud base, the type shall be reported as Cumulonimbus only."
  • 10.2.19 - Revised note to read: "Late weather observation shall be recorded first in Column 41 as a general weather remark (See 10.2.19.14.1)"
  • 10.2.19.8.1 - Revised to read: "If clouds which indicate unstable conditions (CB, TCU or ACC) are observed and not reported in Column 40, they shall be reported in Remarks"
  • 16.3.13.2.4 - Added note to examples of sky condition remarks for convective clouds: “If TCU or CB clouds base are not observed and not reported in the sky condition, they shall be reported in Remarks.”

Runway Visual Range (RVR)

  • 10.2.19.13 - Revised to read: "...Stations with the capability to display values for multiple RVR's may record and transmit a maximum of four RVR values and may include RVR data for runway(s) other than the active or most-aligned into-the-wind. ..."
  • 10.6.1 - Changed RVR Remarks at given times to read: 0539Z OBS: RVR RWY 15 3500FT; 0548Z OBS: RVR RWY 15 3500 FT
  • 10.6.2 - Changed RVR Remarks at given times to read: 0700Z OBS: RVR RWY 15 1800FT; 0900Z OBS: RVR RWY 15 1600FT
  • 13.8.2 - Changed RVR Remark at 0900Z to read: /S08/ RVR RWY15 1600FT
  • 16.3.7 - Revised for clarity (Effective May 2016)

Synoptic Coding

  • 11.3; 11.4 - The following groups from Section 3 have been enclosed in square brackets "[ ]" to signify they are not reported in Canada: [5EEEiE] [55SSS j5F24F24F24F24] [8NsChshs]
  • 12.3.2.1.2; 12.3.11.3.7; 12.4.10.2.1 - Inserted Code Table for N, Nh and Ns in oktas
  • 12.3.2.1.4 (2) - Revised to include: "...or summation amount of 8/8"
  • 12.3.11.5.1 - Revised to read: "CM = /: If CM clouds invisible owing to continuous layer of lower clouds or because of fog, blowing dust or other similar phenomena."
  • 13.8.1 - Changed 8802X to 8802/

IFR approach and alternate limits for Canadian aerodromes

  • Appendix V - Updated IFR approach and alternate limits for Canadian aerodromes
  • Appendix V - Added two new stations: Yellowknife CYZF; Yorkton Muni CYQV - April 2016 (Effective May 2016)

Wind

  • 7.4.2 - Added "Note: Do not estimate the peak speed of a gust or a squall" (Effective May 2016)
  • 16.3.4 - Note (1): Added "Use the Beaufort scale knots average for the speed." (Effective May 2016)

Appendix III

  • Obstruction to Vision - Added Volcanic Ash (VA) (Effective May 2016)
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