Aviation weather thread

Gaoth Laidir

Freezing rain at Aldergrove atm. Temp & dewpoint just above zero but the grass minimum temperature there was -4 °C by 6 am so the ground surface is probably still well below zero.

METAR EGAA 160920Z 17004KT 9999 -FZRA SCT031 BKN037 01/01 Q1028 REFZRA=

irishgeo

how does fog affect flights?

is a runway safety issue , ie lack of visibility from the tower to taxiways, runways etc?

Can ILS not land in fog?

Negative_G

irishgeo wrote: »

how does fog affect flights?

is a runway safety issue , ie lack of visibility from the tower to taxiways, runways etc?

Can ILS not land in fog?

Fog, which is visible moisture, can greatly reduce visibility laterally and vertically. On a very basic level it is akin to driving your car in fog. You would agree that it can be more hazardous driving in fog than on a clear day, it is no different for pilots?

In order to legally shoot an instrument approach the reported visibility must be above that required as indicated on the chart based on the category of instrument approach you are shooting.

In instances where an airport is experiencing fog, they can impose LVP, low visibility procedures. At its most severe this can mean that only a single aircraft can move at any one time on the airfield. Everything is greatly slowed down for safety reasons which will always cause departure and arrival delays.

In short, it is the lack of visibility for all involved. If you want to read further about it, the crash in cork a few years back it will show you the affect fog can have, along with a relatively inexperienced crew, corporate pressure and bad decision making. It is available on the AAIU website.

irishgeo

Negative_G wrote: »

Fog, which is visible moisture, can greatly reduce visibility laterally and vertically. On a very basic level it is akin to driving your car in fog. You would agree that it can be more hazardous driving in fog than on a clear day, it is no different for pilots?

In order to legally shoot an instrument approach the reported visibility must be above that required as indicated on the chart based on the category of instrument approach you are shooting.

In instances where an airport is experiencing fog, they can impose LVP, low visibility procedures. At its most severe this can mean that only a single aircraft can move at any one time on the airfield. Everything is greatly slowed down for safety reasons which will always cause departure and arrival delays.

In short, it is the lack of visibility for all involved. If you want to read further about it, the crash in cork a few years back it will show you the affect fog can have, along with a relatively inexperienced crew, corporate pressure and bad decision making. It is available on the AAIU website.

i seen the documentary.

JCX BXC

Glasgow airport reporting light snow and -1c at 12:20. Temp here 8.4c. Such a difference over such a short space.

JCX BXC

Fog (prob 40%) with 400m VIS at DUB in the forecast this evening. LVP's play havoc with the operations at DUB, but the airport may be sufficiently quiet to handle all ops with LVP's in place.

Gaoth Laidir

Glasgow International runway is cleared but Prestwick's 03/21 is closed.

Glasgow Interantional (at 1946)

SNOWTAM 0008
A) EGPF
01161946
C) 05 E) 30 F) 5/5/5 G) 3/3/3
T) BRAKING ACTION GOOD/GOOD/GOOD. TAXIWAYS USEABLE WITH
CAUTION, FOLLOW-ME AVAILABLE ON REQUEST

30 metres of runway cleared, 3 mm of wet snow.

Prestiwck (at 1955Z)

SNOWTAM 1616
A) EGPK
01161955
C) 12
F) 6/6/6
G) 1/1/1
N) 6
T) RWY 21/03 CLOSED, E)36M. TAXI WITH CAUTION. APRONS UNTREATED

1 mm slush on RWY12

JCX BXC

Fog has descended on Dublin now. CATIII ILS should take any arrivals without issue. Mornings are never too busy if it does persist.

Gaoth Laidir

Any idea why almost all of Heathrow's metars have corrections (COR) in them? They are always automatic, so if there is human input or correction then the AUTO should not appear, but it still does in all but just one or two.
http://www.ogimet.com/display_metars2.php?lang=en&tipo=ALL&ord=REV&nil=SI&fmt=html&lugar=EGLL&anof=2016&mesf=1&dayf=17&horaf=10&minf=30

METAR COR EGLL 170950Z AUTO 06003KT 9999 OVC035 01/00 Q1027 NOSIG=

Gaoth Laidir

Almost 23,000 minutes (70% of total delays) over Europe are currently due to weather (snow, strong winds). Frankfurt, Munich, Geneva and Zurich the main airports affected.

JCX BXC

Gaoth Laidir wrote: »

Almost 23,000 minutes (70% of total delays) over Europe are currently due to weather (snow, strong winds). Frankfurt, Munich, Geneva and Zurich the main airports affected.

Strong winds?

Frankfurt 8kts
Munich 4kts
Zurich 3kts
Geneva 3kts

Gaoth Laidir

Carnacalla wrote: »

Strong winds?

Frankfurt 8kts
Munich 4kts
Zurich 3kts
Geneva 3kts

No, the list included mostly snow (which was affecting those airports) and strong winds (affecting a few other airports, can't remember which ones were listed).

All info was from Eurocontrol.

https://www.public.nm.eurocontrol.int/PUBPORTAL/gateway/spec/PORTAL.19.5.1.1.40/gwt-detached-view.jsp?_portal_context=/gateway/spec/PORTAL.19.5.1.1.40:/PUBPORTAL/gateway/spec/PORTAL.19.5.1.1.40:TAC:1452988800000:0:1453062122349:0:&_view_id=ANM_DETACHED_LIST&_parameter_set_id=&_dataset_info=

EDIT: Heathrow below FL245 and both Istanbul airports.

Gaoth Laidir

Washington Dulles not quite VFR!

KIAD 221952Z 04005KT 1/2SM R01R/2600V3000FT SN FZFG VV007 M05/M07 A3014 RMK AO2 TWR VIS 2 1/2 SLP211 SNINCR 1/1 P0005 T10501067

Visibility ½ mile, RVR Runway 01R is 2600-3000 feet, moderate snow and freezing fog, vertical visibility 700 feet, altimeter 30.14" Hg.
Remark: Automatic station with precipitation measurement, tower visibility 2.5 miles, sea-level pressure 1021.1 hPa, snow increasing, precipitation 0.05 inches, temperature/dewpoint -5.0/-6.7 °C.

KIAD 221721Z 2218/2324 05005KT 3/4SM -SN OVC008
FM222000 05006KT 1/2SM SN OVC003
FM222200 04008KT 1/4SM +SN OVC002
FM230000 04012G20KT 1/4SM +SN OVC002
FM230500 02015G25KT 1/4SM +SN BLSN OVC002
FM231200 36022G35KT 1/4SM +SN BLSN OVC002
FM231800 36015G25KT 1/4SM +SN BLSN OVC002

Forecasting ¼ mile visiblity in heavy drifting and blowing snow from 22Z.

Gaoth Laidir

The French will be striking again on Tuesday. Delays and cancellations at many French airports are likely.

From Eurocontrol:

23/1/2016 07:06
A French public services strike has been announced for next Tuesday 26th January 2016.
The action will start on Monday 25th Jan at 1800utc and end on Wednesday 27th Jan at 0500utc.

Further details in the following Notams    F0101  -   A0234  -   A0235

Airlines are requested to prepare a 20% flight reduction program for Tuesday 26th Jan for each of the following airports:
LFPG, LFPO, LFOB, LFLL, LFMN, LFML, LFBD, LFBO, LFRS.
The activation of this flight reduction program will be decided on Monday during the next DGAC teleconference.
 
Next DGAC teleconference:
Monday 25th Jan at 13:00utc.
Call number : 01.48.50.50.8
Participant pin code : 34835821 #
 
NMOC Brussels

Gaoth Laidir

Snowing hard at Newark now. 3 inches in the past hour and 11 inches on the ground.

METAR:
KEWR 231351Z 03021G28KT 1/16SM R04R/1400FT +SN BLSN VV003 M03/M04 A2974 RMK AO2 PK WND 05034/1328 TWR VIS 1/8 SLP069 SNINCR 3/11 P0007 T10331039 $

JCX BXC

11 inches I dread to think of it!

Gaoth Laidir

Carnacalla wrote: »

11 inches I dread to think of it!

Up to 17 inches now and still rising!

METAR:
KEWR 231751Z 02020G31KT 1/4SM +SN BLSN VV005 M03/M03 A2962 RMK AO2 PK WND 03034/1657 SLP031 SNINCR 2/17 931100 4/017 933012 60067 T10281028 11028 21039 56029 RVRNO

JCX BXC

Wind is a fairly brisk 260 degrees 31kts mean speed at DUB according to the 2pm TAF. Should make a nice bumpy landing for PAX today.

b757

Carnacalla wrote: »

Wind is a fairly brisk 260 degrees 31kts mean speed at DUB according to the 2pm TAF. Should make a nice bumpy landing for PAX today.

Why is that?

JCX BXC

Even at a direct headwind, descending into wind like that is usually bumpy from experience.

b757

(IRELAND) EISN SIGMET 01 VALID 280940/281200 EINN- EISN SHANNON FIR SEV TURB FCST W OF W01030 SFC/FL060 MOV E AT 35KT INTSF=
(IRELAND) EIDW AD WRNG 01 VALID 281300/281600 SFC WIND SW 25-30KT MAX 40-45 FCST =
(IRELAND) EIDW AD WRNG 01 VALID 281300/281600 SFC WIND SW 25-30KT MAX 40-45 FCST =
(IRELAND) EICK AD WRNG 01 VALID 281200/281400 SFC WIND SW 20-25KT MAX 35-40 FCST =
(IRELAND) EINN AD WRNG 01 VALID 281200/281500 SFC WIND SW 20-25KT MAX 35-40 FCST =
(IRELAND) EIME AD WRNG 01 VALID 281100/281700 SFC WIND SW 25-30KT MAX 40-45 FCST =
(IRELAND) EIME AD WRNG 01 VALID 281100/281700 SFC WIND SW 25-30KT MAX 40-45 FCST =
(IRELAND) EIKN AD WRNG 01 VALID 281030/281500 SFC WIND SW 25-30KT MAX 40-45 FCST =
(IRELAND) EIKN AD WRNG 01 VALID 281030/281500 SFC WIND SW 25-30KT MAX 40-45 FCST =

Gaoth Laidir

Warnings out for areas of severe low-level turbulence shooting eastwards at 50 knots tonight. That is a pretty high forward speed for a frontal system and one reason why I think some of the TAFs may be underdone a little.

• EISN SIGMET 07 VALID 282100/282300 EINN- EISN SHANNON FIR SEV TURB FCST W OF LINE N5520 W00810 - N5100 W01230 SFC/FL060 MOV E AT 50KT NC=
• EISN SIGMET 06 VALID 281800/282200 EINN- EISN SHANNON FIR SEV MTW FCST W OF LINE N5434 W01000 - N5100 W00800 FL060/200 MOV E AT 50KT INTSF=
• EINN AD WRNG 02 VALID 282300/290700 SFC WIND SW 25-30KT MAX 40-45 BECMG OCNL 2903/2907 30-35 MAX 45-50 =
• EIKN AD WRNG 02 VALID 282300/290800 SFC WIND SW 20-25KT MAX 35-40 BECMG 2901/2903 25-30 MAX 45-50 BECMG 2905/2907 W 25-30 MAX 40-45 =
• EIME AD WRNG 02 VALID 282300/290900 SFC WIND SW 25-30KT MAX 35-40 BECMG 2900/2902 30-35 MAX 45-50 BECMG 2907/2909 W 20-25 MAX 35-40=
• EICK AD WRNG 02 VALID 290000/290800 SFC WIND SW 25-30KT MAX 40-45=
• EIDW AD WRNG 02 VALID 290000/291300 SFC WIND SW 25-30KT MAX 40-45 BECMG OCNL 2902/2907 25-30 MAX 45-50 BECMG 2907/2909 W 40-45 281950=

JCX BXC

11pm TAF upgrades the wind at DUB.

BECMG 2am-5am 230° 28kts G 46kts
TEMPO 5am-7am 230° 32kts G 51kts

Some disruption possible, but unlikely as wind after 7am switches more westerly and weakens.

SNN has
TEMPO 3am-6am 240° 33kts G 50kts. Direct headwind and things have often landed in gusts up to 60kts.

ORK has a little wind early in the night but mostly gone by the time the morning comes.

NOC 11pm TAF isn't available yet.

---

Belfast has some fairly brisk winds!

TEMPO 4am-8am 210° 40kts G 58kts with Rain Drizzle and Heavy Rain

And later in the evening

Prob 40% 8pm-12am TEMPO
250° 35kts G 45kts 1200m showers Rain Snow and Snow.

Gaoth Laidir

What did I tell ya!

Gaoth Laidir

Gust of 62 knots at Sligo Airport.

SPECI EISG 290441Z AUTO 22039G62KT 5000 -DZ FEW011 BKN024 OVC031 11/08 Q0996=

The 2am TAF called for just 52 knots.

TAF EISG 290200Z 2903/2912 22026G46KT 9999 -RA SCT012 BKN020 TEMPO 2903/2905 23032G52KT 4000 RA BKN010 BECMG 2905/2907 26027G45KT BECMG 2907/2909 26023G37KT BECMG 2909/2912 24022G33KT=

Gaoth Laidir

68 knots at Mace Head (Connemara)

PsMETAR MACE 290500Z AUTO 25043G68KT 5000NDV -SHRA BKN010/// BKN050/// 10/08 1002 MSL=

Gaoth Laidir

Snow showers forecast for Knock and Aldergrove (PROB40) overnight tonight.

●TAF EIKN 290500Z 2906/3006 26026G43KT 9999 FEW020 BKN030 BECMG 2907/2909 25020G33KT BECMG 2916/2918 23022G33KT TEMPO 2916/2920 4000 -SHRA BKN007 BECMG 2918/2920 26021G33KT TEMPO 3000/3006 3000 -SHSN BKN005 =
●TAF EGAA 290459Z 2906/3006 22030G45KT 9999 FEW018 SCT025 BECMG 2906/2909 24022G32KT TEMPO 2906/2908 22040G58KT 4000 +RA +SHRA BKN010 PROB40 TEMPO 2908/2918 24032G45KT 6000 SHRA PROB40 TEMPO 2918/3006 25032G45KT 1200 SHGS SHSN BKN004 BECMG 3003/3006 26015G25KT=

Gaoth Laidir

48 gust 69 knots at Donegal Airport now

SPECI EIDL 290537Z AUTO 25048G69KT 5000 +DZ FEW012 BKN026 OVC037 10/05 Q0994=

JCX BXC

Sleet showers in the SNN forecast too.

JCX BXC

Dublin airport reporting Smoke? At 09:30