Japan Spectral Model (JSM) was developed for operational forecast use in JMA. The model is a 19-level spectral limited-area model with a horizontal resolution of 40km. The purpose of the model is to predict meso-*-scale phenomena and fine structures of orographically induced disturbances.The model predicts quite well the mesoscale structure within a synoptic scale disturbance and the evolution of a mesoscale cloud system associated with a polar low. The model also shows sufficient ability to predict severe rainfalls in the Baiu season.Forecasts of precipitation show a good performance in spring even in the early hours of the forecast time. However, the scores for the summer season are worse than those for spring. This may be due to the cumulus parameterization scheme used in JSM. Slow spin up of the model is a serious problem in the summer season.

A spectral limited-area primitive-equation model with a time-dependent lateral boundary condition is described. The model is nested in one way to a low resolution model. A spectral representation of the horizontal fields of prognostic variables is performed by introducing a modified double Fourier series. This series is composed of the usual orthogonal double Fourier series, that is suitable for prediction in the limited-area with a free-slip wall boundary condition, and a few additional bases by which the boundary condition which does not belong to the wall condition will be satisfied. Fluxes of mass, momentum, energy, etc. across the boundary can be specified using the additional bases. The

Carrot sticks that were prepared with a sharp culinary knife exhibited a whitish translucent appearance on the surface. This condition was not readily apparent with carrot sticks sliced with a razor sharp blade. Scanning electron microscopic examination of the translucent tissue revealed that the knife tended to shear, separate and compress the cells and tissues of the root. Dehydration of the large mass of exposed cells probably was responsible for the appearance of the whitish translucent tissue. Development of this condition is undesirable because consumers associate this with aged or nonfresh carrot sticks.

Real data forecast experiments of heavy rainfalls in Baiu front (a front in the Asian subtropical humid region) are made for two typical cases by using a 6-level 77km-mesh regional primitive equation model. We show first that the moist convective adjustment scheme which has bcen used in coarse-mesh models is not always suitable for the present model as the scheme tends to produce heavy rainfalls in the area far south to the frontal zone. In order to confine heavy rainfalls within the frontal zone or in the vicinity of frontal disturbances, we improved the scheme by controling the adjustment through low-level vorticity and by modifying the critical lapse rate used in the scheme. Detailed analysis is made for two cases of Baiu frontal heavy rainfalls predicted by the model including the improved adjustment scheme. The characteristic features of Baiu front associated with heavy rainfalls (i.e., concentration of heavy rainfalls in a zone to the south of subtropical jet stream, formation of a low-level strong wind zone to the south of the heavy rainfall zone, moist tongue and a zone of convective warming in the middle troposphere) are accurately predicted.

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