Various Features Influencing Convection Initiation on 12 June 2002 during IHOP_2002* Tammy M. Weckwerth Tammy M. Weckwerth (NCAR) WWRP Symposium on Nowcasting and Very Short Range Forecasting, Toulouse, France, 5-9 September 2005 *Work in Progress Hanne V. Murphey Hanne V. Murphey (UCLA) Cyrille Flamant Cyrille Flamant (CNRS) Crystalyne R. Pettet Crystalyne R. Pettet (US NWS) Roger M. Wakimoto Roger M. Wakimoto (NCAR) Sophie Bastin Sophie Bastin (NCAR)
15
Embed
Tammy M. Weckwerth Various Features Influencing Convection Initiation on 12 June 2002 during IHOP_2002* Tammy M. Weckwerth (NCAR) WWRP Symposium on Nowcasting.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Various Features Influencing Convection Initiation on
12 June 2002 during IHOP_2002*
Tammy M. WeckwerthTammy M. Weckwerth (NCAR)
WWRP Symposium on Nowcasting and Very Short Range Forecasting, Toulouse, France, 5-9 September 2005
*Work in Progress
Hanne V. MurpheyHanne V. Murphey (UCLA)Cyrille FlamantCyrille Flamant (CNRS)
Crystalyne R. PettetCrystalyne R. Pettet (US NWS) Roger M. WakimotoRoger M. Wakimoto (NCAR)
Sophie BastinSophie Bastin (NCAR)
GOES 11
Composite Radar
3117
3119
3117
3318
3417 34
16
3413
3217
3216
3323
3520
3619
3719
3912
3615
3314
33
3418
3720
3519
3519
3721
3522
3523
3523
3421
3323
36
3021
2923
3321
50 km
101 100o 99 98
38
37o
36
12 June 2002
Are the intersections between the waves and outflow preferred regions for CI?
Why did CI occur here?
Are the rolls a factor in CI?
Does the mesolow play a role in CI?
2050 UTC
CI 19 km from drop line
• Incomplete soundings – only up to 6 km AGL (445 mb)• No drops in CI air mass
NE SW
Outflow boundary
Dropsonde Leg 2 – CAPE & CIN
ELDORA Observations of Waves
• ELDORA fields @ 900 m AGL• Gravity waves in all fields: λ = 6-8 km• Consistent with P-3, MIPS, GOES-11 and radar
dBZe vr
div vort
ELDORA and Leandre II Wave Impacts
• ELDORA and Leandre II fields @ 400 m AGL• Periodic signature in q, div and vort: λ=6-8 km
km
OK Mesonet – 18 UTC – Mesolow Impact
• LLJ feeding region of interest• Dewpoints in the high 60s and low 70s
Freedom
Wind Direction
Wind Speed Mixing Ratio
Moisture Convergence
Freedom, OK MesonetMesolow Impact
• Local increase in southerly flow, perhaps due to mesolow – not observed further south
• Increase in moisture convergence
Roll Observations
• ELDORA reflectivity and winds @ 400 m AGL• 1.1 km in situ fields show rolls (λ~3.6 km) SE of TP
qθ
w10 km
Preliminary results• Mesolow may have aided in enhancing moisture convergence in CI region.
• Waves sampled by ground-based radar, satellite, in situ P-3, low-level MIPS w, ELDORA. Suggestion of Leandre II mixing ratio modulation caused by waves – may be important for CI.
• Rolls observed near CI location with radar and in-situ P-3 – may be important for CI.*
3117
3119
3117
3318
3417 34
16
3413
3217
3216
3323
3520
3619
3719
3912
3615
3314
33
3418
3720
3519
3519
3721
3522
3523
3523
3421
3323
36
3021
2923
3321
50 km
101 100o 99 98
38
37o
36
GOES-11 Cloud Tracking
• 1st clouds formed along rolls
• Northern cloud formed near wave/outflow intersection
Ongoing work• Closely examine ELDORA and Leandre II measurements near CI location
• Modeling study by Sophie Bastin (presented next)