blended course on the principles of satellite meteorology 21 st april – 15 th july 2009 classroom...

Blended Course on the Principles of Satellite Meteorology

21st April – 15thJuly 2009

Classroom 15-19 June 2009

Final Presentation – Convection – 09May2009

Ângela Lourenço – Portugal [email protected]

June2009 1Ângela Lourenço

mailto:[email protected]


Convective cell over central part of Portugal



1.Synoptic Situation & Relevant Conceptual Model

2.Satellite Images

3.Observations



Synoptic Situation – Analysis - 090000UTC

Mean sea level pressure and 10m horizontal wind

500hPa height, temperature and wind


Continental Portugal was under the influence of a weak ridge and a low west of Morocco and at middle and high levels by the upper branch of a trough.



Satrep Online – 090600UTC (run 081200UTC)

Thickness_850/500Conv1000 θe_850 Showalter

Ridge in equivalent thickness between the two pressure level (mainly over Spain).

Convergence at 1000hPa west of Morocco.

High values of equivalent potential temperature.

Unstable region southeast of Portugal.


Blended Course on the Principles of Satellite MeteorologySynoptic Situation – Analysis - 091200UTC

Mean sea level pressure and 10m horizontal wind



The high pressure system drifted towards France while the low moved northwards and slightly deepened. The trough at high levels was almost stationary although at 300hPa there was a local minimum just southwest of Continental Portugal.



Satrep Online – 091200UTC (run 081200UTC)

Thickness_850/500

Conv1000

θe_850

Showalter

The area of convergence at 1000hPa moves further north.

Unstable region is bigger. Showalter index is lower than zero over south of Portugal.

Ridge in equivalent thickness between the two pressure levels .




SatRep Online – 1800UTC (run 081200UTC

Conv1000

Thickness_850/500

Showalter

θe_850

The area of convergence at 1000hPa has not change considerably.

Unstable region is more define. Showalter index is lower than zero over Portugal (very unstable over Spain).

Ridge in equivalent thickness between the two pressure levels.




0600UTC 1200UTC1800UTC

1200UTC 1800UTC

Global Instability Index (LI)

mm

Total Precipitable Water




Conceptual Model: Cb Cluster

Key Parameters:a)Thickness ridgeb)Thetaw850 ridgec)Unstable (Showalter Index)d)Low level divergence

Cb Cluster developed in warm air of a thermal ridge. It started to organize over sea, southwest of Lisbon around 10-12UTC then it moved slowly northeastward, had its mature stage between 16 and 17UTC, then its movement drifted north and decayed later in the evening.

09may2009 – 1800UTC


1600UTC

Lisbon

Lisbon

High Resolution Visible (HRV – Channel 12)At this time is possible to detect an overshooting.

Severe Convection RGB (WV6.2-WV7.3, IR3.9-IR10-8, NIR1.6-VIS0.6). High level cloud with ice particles where some yellowish pixels can indicate cell’s development and the presence of small ice particles but large ice particles (red and orange) are dominant and there are not bright yellow spots.

Radar image with dBz values between 52 and 56.


Blended Course on the Principles of Satellite Meteorology1615UTC

Lisbon

IR10.8 (enhanced) where the colours give the cloud top temperature with areas around -64ºC.

Light orange pixels may indicate the presence of small ice particles. No bright and yellow spots, no intense updrafts.

No visible overshootings at this time.

Severe Convection-RGB

HRV

Maximum dBz values around 56.

Lisbon



1630UTC

Lisbon

No visible overshootings at this time.

Severe Convection-RGB

HRV

IR10.8(enhanced)

Lisbon

Areas with cloud top temperature around -64ºC.

Maximum dBz values around 56.

No significant changes since last image.



1645UTC

Lisbon

Lisbon

Overshooting andevidence of gravity waves at cloud top.

Areas with cloud top temperature around -63ºC.

Maximum dBz values between 56 and 60.

HRV

IR10.8(enhanced) Severe Convection-RGB

In the central region of the cell mainly light orange and yellowish pixels and a yellow spot on the right. Strong updraft.



Radiosonde from Lisbon – 09may2009 - 1200 UTCCAPE: 832 J/kgCIN: -91 J/kgLI: -2.8 ºCTPW: 22.2 mm (until 389hPa)LCL:~975hPaLFC:~800hPaEL:~250hPaCCL:~845hPaConvective Temperature:~25ºCTmax: 23.2ºC(13:20UTC)

Dry layer from surface until 750hPa.



Synoptic ObservationsAlvega08812

Coruche08744

Highest Wind Gust: 75.2 km/h (1530UTC)

Max. Precipitation: 11mm/20min(17/1720 UTC)

Non meteorological reports indicated hail and possible larger amounts of accumulated precipitation.

09may20091600UTC

Lisbon

09may2009

09may2009



090000 – 092400UTC 091600 – 091700UTC

Lightning – 09may2009



HRV – 1500UTC

09may120091533UTC



09may2009 - 15:33UTCLat: 38°59'47.76"NLong: 8°30'42.25"WPhoto : www.meteoalerta.com


http://www.meteoalerta.com/


References:

Satrep Online – http://satreponline.org

SatRep and SatManu – http://www.knmi.nl/satrep

EUMETSAT- http://oiswww.eumetsat.org/IPPS/html/DerivedProducts/MSG2

EUMETSAT- MSG Interpretation Guide - http://www.eumetsat.int

Instituto de Meteorologia, I.P., Portugal - NWP Fields (ECMWF), Radar imagesand Synoptic Observations.

Photo – http://www.meteoalerta.com


blended course on the principles of satellite meteorology 21 st april – 15 th july 2009 classroom...

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