NWS WFOs typically collect twice-daily soundings at 0000 and 1200 UTC from NWS rawinsonde observation
(raob) locations across the country.
The grid was centered on the storm circulation center at each rawinsonde observation
On the left, a rawinsonde observation
(RAOB) from the Aberdeen Proving Ground, Md., (KAPG) shows a thin saturated layer around 5000 feet.
To evaluate the potential value of assimilating TAMDAR observations, model forecasts from the four experiments were compared above the surface against ACARS, TAMDAR, and rawinsonde observations
and at the surface against MADIS standard and mesonet surface observations in addition to maritime observations; additionally precipitation analyses were also used for verification.
As a consequence, PBL wind speed and temperature modeled by CALMET are quite in agreement with estimated from rawinsonde observations
, showing the capability of CALMET model to provide a reasonable upper-air meteorological input to CALPUFF dispersion model.
We next examined the rawinsonde observations
taken twice daily all over the world, as well as the computer modeling that results.
PBL depths can be directly measured using rawinsonde observations
[6-8], tethered balloons , and masts  and using direct measurements from aircraft .
Automated aircraft water vapor reports, provided by 148 aircraft worldwide through the WMO's AMDAR program, are at least as accurate as rawinsonde observations
and have greater influence on 1-2 day NWP forecasts than all other in-situ moisture data over the United States
(1991) compared results including MDCRS data in an 80-km-resolution developmental version of the RUC against equivalent twice-daily forecasts from the NWS's then-operational Nested Grid Model (NGM) that relied primarily on rawinsonde observations
(raobs) for upper-air information.
Satellite and rawinsonde observations
suggest that synoptic-scale dry air advection plays an important role in convective suppression in the tropics (Yoneyama and Parsons 1999; Kerns and Chen 2014b).
However, the overall good agreement between the AERI and rawinsonde observations
shows that AERI observations can be used to monitor the near-surface temperature structure of the atmospheric boundary layer, which is very important for investigating the LLJ development in more detail (see also more details below).
Howard, 2013: The impact of dropwindsonde and supplemental rawinsonde observations
on track forecasts for Hurricane Irene (2011).