同一天下午雷暴的预报,我从早上开始观察和12个z <一口> __ < /一口>模式运行。特别是我从12个z GFS和不结盟运动的输出,然后给一些时间传播到说唱最后HRRR模型初始化开始互相GFS。对于观测数据,我感兴趣的12个z气球,表面字段(温度、露点、风速、压力),上层大气数据(850 mb温度、500 mb风能和涡度、300 mb风)和卫星图像(云量)。12个z早上试探会经常会有残余的夜间边界层反演和前面的天。给云层和表面温度和水分平流你可以得到一个粗略的边界层会如何演变。12 z GFS后一两个小时,不结盟运动将开始进来,你可以看看预测调查和模型认为事情会如何演变。在15-17Z我看着HRRR一些额外的指导。——好望角,风切变只能告诉这个故事的一部分。角(对流可用势能)是一种测量浮力和它的反面,CIN(对流抑制)是衡量一个包裹必须克服负浮力的达到其水平自由对流。你可以有很多的斗篷,但多一点CIN可以阻止任何雷暴射击。 If you have no CIN on the other hand but lots of CAPE you'll generally get a mess of storms everywhere but nothing organized. The bulk 0-6 km wind shear is a good predictor of the type of storms you can anticipate. Little shear tends toward air-mass thunderstorms while lots of shear tends toward supercell thunderstorms. In between these two are multi-cell thunderstorms. The shear will also influence whether multiple storms along a boundary stay discrete or build upscale into a linear feature (e.g. squall lines or QLCS). What the above things tell you is whether the environment favors convection and what type of convection. It does not tell you if there will be a storm or not. You can have a perfect environment for storms, but unless something acts to initiate convection, you won't have a storm. Storms like to initiate along boundaries (cold fronts, dry lines, gust fronts, etc). You can also initiate with daytime thermal boundary layer convection eroding CIN until parcels can freely convect. Upper level divergence can also promote initiation by providing large scale ascent. --- Putting this together, I'm looking at observations and model output to identify favorable storm environments. I'm also looking at them for features that promote initiation. As we near showtime, I'll also be looking at radar. On the radar I'm looking for evidence of convergence zones (radar fine lines, fronts, etc) to narrow down where I'd expect storms to fire. --- † The *Z* suffix is shorthand for the historical Zulu time zone, which in modern times we call GMT or Greenwich Mean Time. All meteorological products are referenced to this time zone and this is done for simplicity. For example, no matter where you are on Earth, you know balloons are going to go up at 12Z and 00Z, and that the GFS will come out at 00,06,12 and 18Z. The conversion to local time exactly that as from GMT or UTC. For example 12Z on the east coast of the USA (in eastern *daylight* time, EDT, at the time of this writing) is GMT-0400, so 12Z - 4 = 08, or 8 AM EDT (and 7 AM EST the other half of the year).